diff --git a/app/src/main/java/net/osmtracker/GitHubUser.java b/app/src/main/java/net/osmtracker/GitHubUser.java
index d1e387e31..e6ce5b5cf 100644
--- a/app/src/main/java/net/osmtracker/GitHubUser.java
+++ b/app/src/main/java/net/osmtracker/GitHubUser.java
@@ -1,33 +1,30 @@
 package net.osmtracker;
 
+import net.osmtracker.github.*;
+
 import android.content.Context;
 import android.content.SharedPreferences;
 
 public class GitHubUser {
-
-    private static final String PREF_NAME = "GitHubPrefs";
-    private static final String KEY_USERNAME = "username";
-    private static final String KEY_TOKEN = "token";
-
     private SharedPreferences sharedPreferences;
 
     public GitHubUser(Context context) {
-        sharedPreferences = context.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
+        sharedPreferences = context.getSharedPreferences(GitHubConstants.SHARED_PREFS_NAME, Context.MODE_PRIVATE);
     }
 
     public void saveCredentials(String username, String token) {
         sharedPreferences.edit()
-                .putString(KEY_USERNAME, username)
-                .putString(KEY_TOKEN, token)
+                .putString(GitHubConstants.KEY_USERNAME, username)
+                .putString(GitHubConstants.KEY_TOKEN, token)
                 .apply();
     }
 
     public String getUsername() {
-        return sharedPreferences.getString(KEY_USERNAME, "");
+        return sharedPreferences.getString(GitHubConstants.KEY_USERNAME, "");
     }
 
     public String getToken() {
-        return sharedPreferences.getString(KEY_TOKEN, "");
+        return sharedPreferences.getString(GitHubConstants.KEY_TOKEN, "");
     }
 
     public boolean hasCredentials() {
diff --git a/app/src/main/java/net/osmtracker/activity/GitHubConfig.java b/app/src/main/java/net/osmtracker/activity/GitHubConfig.java
index d094d0516..3514f1211 100644
--- a/app/src/main/java/net/osmtracker/activity/GitHubConfig.java
+++ b/app/src/main/java/net/osmtracker/activity/GitHubConfig.java
@@ -14,11 +14,9 @@
 
 import net.osmtracker.GitHubUser;
 import net.osmtracker.R;
+import static net.osmtracker.github.GitHubConstants.GITHUB_TOKENS_URL;
 
 public class GitHubConfig extends Activity {
-
-    private final static String GitHubToken_URL = "https://github.com/settings/tokens";
-
     EditText editTextUserName, editTextUserToken;
     private GitHubUser gitHubUser;
 
@@ -37,7 +35,7 @@ protected void onCreate(Bundle savedInstanceState) {
             @Override
             public void onClick(View v) {
                 Intent intent = new Intent(Intent.ACTION_VIEW);
-                intent.setData(Uri.parse(GitHubToken_URL));
+                intent.setData(Uri.parse(GITHUB_TOKENS_URL));
                 startActivity(intent);
             }
         });
@@ -49,12 +47,15 @@ public void onClick(View v) {
                 String username = editTextUserName.getText().toString().trim();
                 String ghToken = editTextUserToken.getText().toString().trim();
 
+                // Empty is enabled to allow saving without credentials to erase the existing ones
+                /*
                 if (username.isEmpty()) {
                     editTextUserName.setError("Username required");
                     return;
                 }
-                if (ghToken.length() != 40) {
-                    editTextUserToken.setError("Token must be 40 characters");
+                */
+                if (ghToken.length() != 40 && !ghToken.isEmpty()) {
+                    editTextUserToken.setError(getString(R.string.error_gh_token_lenght));
                     return;
                 }
 
diff --git a/app/src/main/java/net/osmtracker/activity/GitHubNewFork.java b/app/src/main/java/net/osmtracker/activity/GitHubNewFork.java
index bf8d6d551..e6ffa4e1f 100644
--- a/app/src/main/java/net/osmtracker/activity/GitHubNewFork.java
+++ b/app/src/main/java/net/osmtracker/activity/GitHubNewFork.java
@@ -21,6 +21,7 @@
 
 import net.osmtracker.GitHubUser;
 import net.osmtracker.R;
+import static net.osmtracker.github.GitHubConstants.getRepoForksUrl;
 
 import org.json.JSONException;
 import org.json.JSONObject;
@@ -29,9 +30,7 @@
 import java.util.Map;
 
 public class GitHubNewFork extends Activity {
-
     EditText editTextRootUsername, editTextRootRepo;
-    private String BaseURL = "https://api.github.com";
     private GitHubUser gitHubUser;
     private String newForkFullName;
 
@@ -69,7 +68,6 @@ public void onClick(View v) {
                 createNewFork(username, repo);
                 //Toast.makeText(GitHubNewFork.this, R.string.successfully_created, Toast.LENGTH_SHORT).show();
                 //finish();
-
             }
         });
 
@@ -78,7 +76,6 @@ public void onClick(View v) {
         btnCancel.setOnClickListener(new OnClickListener() {
             @Override
             public void onClick(View v) {
-
                 finish();
             }
         });
@@ -88,7 +85,7 @@ public void onClick(View v) {
     }
 
     private void createNewFork(String username, String repo) {
-        String fullURL = getBaseURL() + "/repos/"+ username +"/"+ repo +"/forks?name=fork";
+        String fullURL = getRepoForksUrl(username, repo);
 
         JsonObjectRequest  postResquest= new JsonObjectRequest(
                 Request.Method.POST,
@@ -119,15 +116,10 @@ public Map getHeaders() throws AuthFailureError
                 headers.put("Authorization", "Bearer " + gitHubUser.getToken());
                 return headers;
             }
-
         };
         Volley.newRequestQueue(this).add(postResquest);
     }
 
-    public String getBaseURL() {
-        return BaseURL;
-    }
-
     public void setNewForkFullName(String newForkFullName) {
         this.newForkFullName = newForkFullName;
     }
diff --git a/app/src/main/java/net/osmtracker/activity/GitHubNewRepo.java b/app/src/main/java/net/osmtracker/activity/GitHubNewRepo.java
index 51f0823c6..4be491618 100644
--- a/app/src/main/java/net/osmtracker/activity/GitHubNewRepo.java
+++ b/app/src/main/java/net/osmtracker/activity/GitHubNewRepo.java
@@ -22,6 +22,7 @@
 
 import net.osmtracker.GitHubUser;
 import net.osmtracker.R;
+import static net.osmtracker.github.GitHubConstants.GITHUB_API_USER_REPOS_URL;
 
 import org.json.JSONException;
 import org.json.JSONObject;
@@ -33,7 +34,6 @@
 public class GitHubNewRepo extends Activity {
 
     EditText editTextNewRepo;
-    private String BaseURL = "https://api.github.com";
     private GitHubUser gitHubUser;
     private String newRepoFullName;
 
@@ -77,7 +77,7 @@ public void onClick(View v) {
     }
 
     private void createNewRepo(String repoName, boolean isPrivate) {
-        String fullURL = getBaseURL()+"/user/repos";
+        String fullURL = GITHUB_API_USER_REPOS_URL;
 
         ProgressDialog progressDialog = new ProgressDialog(this);
         progressDialog.setMessage(this.getResources().getString(R.string.github_creating_repository));
@@ -140,10 +140,6 @@ public byte[] getBody() {
         Volley.newRequestQueue(this).add(postResquest);
     }
 
-    public String getBaseURL() {
-        return BaseURL;
-    }
-
     public void setNewRepoFullName(String newRepoFullName) {
         this.newRepoFullName = newRepoFullName;
     }
diff --git a/app/src/main/java/net/osmtracker/activity/GitHubPullRequest.java b/app/src/main/java/net/osmtracker/activity/GitHubPullRequest.java
index 80033c1d4..85198674e 100644
--- a/app/src/main/java/net/osmtracker/activity/GitHubPullRequest.java
+++ b/app/src/main/java/net/osmtracker/activity/GitHubPullRequest.java
@@ -21,7 +21,10 @@
 
 import net.osmtracker.GitHubUser;
 import net.osmtracker.R;
+import static net.osmtracker.github.GitHubConstants.getRepoPullsUrl;
+import static net.osmtracker.github.GitHubConstants.getRepoUrl;
 
+import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
 
@@ -32,9 +35,8 @@
 public class GitHubPullRequest extends Activity {
 
     EditText editTextTitle, editTextBody;
-    private String BaseURL = "https://api.github.com";
-    private String RepoOrigen;
-    private String DefaultBranch;
+    private String repoOrigen;
+    private String defaultBranch;
     private GitHubUser gitHubUser;
 
     @Override
@@ -84,7 +86,7 @@ public void onClick(View v) {
     }
 
     private void createPullRequest() {
-        String fullURL = getBaseURL()+"/repos/"+getRepoOrigen()+"/pulls";
+        String fullURL = getRepoPullsUrl(this.repoOrigen);
 
         JsonObjectRequest postResquest= new JsonObjectRequest(
                 Request.Method.POST,
@@ -103,14 +105,23 @@ public void onResponse(JSONObject response) {
                 }, new Response.ErrorListener() {
             @Override
             public void onErrorResponse(VolleyError error) {
-                String errorMsg = "Error while creating the PR";
+                String errorMsg = "";
                 if (error.networkResponse != null && error.networkResponse.data != null) {
                     try {
                         String responseBody = new String(error.networkResponse.data, "utf-8");
                         Log.e("PR_ERROR", responseBody);
-                        errorMsg += "\n" + responseBody;
+                        JSONObject github_response = new JSONObject(responseBody);
+                        JSONArray github_errors = github_response.getJSONArray("errors");
+                        for (int i = 0; i < github_errors.length(); i++) {
+                            JSONObject github_error = github_errors.getJSONObject(i);
+                            errorMsg += github_error.getString("message") + "\n";
+                        }
                     } catch (UnsupportedEncodingException e) {
                         e.printStackTrace();
+                    } catch (JSONException e) {
+                        e.printStackTrace();
+                    } finally {
+                        errorMsg += getString(R.string.error_gh_pr_creation);
                     }
                 }
                 Toast.makeText(GitHubPullRequest.this, errorMsg, Toast.LENGTH_LONG).show();
@@ -154,7 +165,7 @@ public byte[] getBody() {
     }
 
     private void getInfoRepo(String repoFullName) {
-        String fullURL = getBaseURL()+"/repos/"+repoFullName;
+        String fullURL = getRepoUrl(repoFullName);
 
         JsonObjectRequest postResquest= new JsonObjectRequest(
                 Request.Method.GET,
@@ -187,23 +198,16 @@ public Map getHeaders() throws AuthFailureError {
         Volley.newRequestQueue(this).add(postResquest);
     }
 
-    public String getBaseURL() {
-        return BaseURL;
-    }
-
-    public String getRepoOrigen() {
-        return RepoOrigen;
-    }
 
     public void setRepoOrigen(String repoOrigen) {
-        RepoOrigen = repoOrigen;
+        this.repoOrigen = repoOrigen;
     }
 
     public String getDefaultBranch() {
-        return DefaultBranch;
+        return defaultBranch;
     }
 
     public void setDefaultBranch(String defaultBranch) {
-        DefaultBranch = defaultBranch;
+        this.defaultBranch = defaultBranch;
     }
 }
diff --git a/app/src/main/java/net/osmtracker/activity/GitHubUpload.java b/app/src/main/java/net/osmtracker/activity/GitHubUpload.java
index 150adab6f..07f265413 100644
--- a/app/src/main/java/net/osmtracker/activity/GitHubUpload.java
+++ b/app/src/main/java/net/osmtracker/activity/GitHubUpload.java
@@ -34,6 +34,8 @@
 import net.osmtracker.util.Callback;
 import net.osmtracker.util.DialogUtils;
 import net.osmtracker.util.GitHubUtils;
+import static net.osmtracker.github.GitHubConstants.getRepoFileContentUrl;
+import static net.osmtracker.github.GitHubConstants.getUserReposUrl;
 
 import org.json.JSONArray;
 import org.json.JSONException;
@@ -50,9 +52,7 @@
 
 
 public class GitHubUpload extends Activity {
-
     private ArrayList<String> ArrayListRepos;
-    private String BaseURL = "https://api.github.com";
     private GitHubUser gitHubUser;
     private String  RepoName = "";
     EditText editTextCommitMsj;
@@ -166,7 +166,7 @@ private void openActivityOnClick(int btnId, Class<? extends Activity> destinatio
      * Either starts uploading directly if we are authenticated against GitHub
      */
     private void startUploadGitHub(final String fileInBase64, String filename, String commitMsj){
-        String fullURL = getBaseURL()+"/repos/"+getRepoName()+"/contents/"+filename;
+        String fullURL = getRepoFileContentUrl(getRepoName(), filename);
 
         ProgressDialog progressDialog = new ProgressDialog(this);
         progressDialog.setMessage(this.getResources().getString(R.string.uploading_file) + filename);
@@ -264,15 +264,19 @@ public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l)
             }
             @Override
             public void onNothingSelected(AdapterView<?> adapterView) {
-
+                Toast.makeText(GitHubUpload.this, "R.string.upload_to_github_select_repo", Toast.LENGTH_SHORT).show();
             }
         });
     }
 
     private void listRepos() {
+        ProgressDialog progressDialog = new ProgressDialog(this);
+        progressDialog.setMessage(getString(R.string.retrieving_repositories));
+        progressDialog.setCancelable(true);
+        progressDialog.show();
+
         RequestQueue queue = Volley.newRequestQueue(this);
-        String sortBy = "created";
-        String fullURL = getBaseURL() + "/user/repos?" + "sort=" + sortBy ;
+        String fullURL = getUserReposUrl();
 
         JsonArrayRequest getResquest = new JsonArrayRequest(
                 Request.Method.GET,
@@ -281,17 +285,7 @@ private void listRepos() {
                 new Response.Listener<JSONArray>() {
                     @Override
                     public void onResponse(JSONArray response) {
-                        for (int i = 0; i < response.length(); i++) {
-                            // creating a new json object and
-                            // getting each object from our json array.
-                            try {
-                                JSONObject responseObj = response.getJSONObject(i);
-                                ArrayListRepos.add(responseObj.getString("full_name"));
-
-                            } catch (JSONException e) {
-                                e.printStackTrace();
-                            }
-                        }
+                        listRepoResponseAction(response, progressDialog);
                     }
                 }, new Response.ErrorListener() {
             @Override
@@ -318,6 +312,35 @@ public Map getHeaders() throws AuthFailureError
         queue.add(getResquest);
     }
 
+    /**
+     * This method is called when the list of repositories is retrieved
+     * from the server.
+     *
+     * @param response JSONArray with the repositories
+     * @param progressDialog ProgressDialog
+     */
+    private void listRepoResponseAction(JSONArray response, ProgressDialog progressDialog) {
+        boolean errorOcurred = false;
+        for (int i = 0; i < response.length(); i++) {
+            // creating a new json object and
+            // getting each object from our json array.
+            try {
+                JSONObject responseObj = response.getJSONObject(i);
+                ArrayListRepos.add(responseObj.getString("full_name"));
+            } catch (JSONException e) {
+                progressDialog.dismiss();
+                Toast.makeText(GitHubUpload.this, R.string.error_retrieving_repositories, Toast.LENGTH_SHORT).show();
+                e.printStackTrace();
+                errorOcurred = true;
+                break;
+            }
+        }
+        if (!errorOcurred) {
+            Toast.makeText(GitHubUpload.this, R.string.successfully_retrieved_repositories, Toast.LENGTH_SHORT).show();
+            progressDialog.dismiss();
+        }
+    }
+
     public String getRepoName() {
         return RepoName;
     }
@@ -325,9 +348,4 @@ public String getRepoName() {
     public void setRepoName(String repoName) {
         RepoName = repoName;
     }
-
-    public String getBaseURL() {
-        return BaseURL;
-    }
-
 }
diff --git a/app/src/main/java/net/osmtracker/github/GitHubConstants.java b/app/src/main/java/net/osmtracker/github/GitHubConstants.java
new file mode 100644
index 000000000..342c1d925
--- /dev/null
+++ b/app/src/main/java/net/osmtracker/github/GitHubConstants.java
@@ -0,0 +1,66 @@
+package net.osmtracker.github;
+
+public final class GitHubConstants {
+    // Config constans
+    public static final String SHARED_PREFS_NAME = "GitHubPrefs";
+    public static final String KEY_USERNAME = "username";
+    public static final String KEY_TOKEN = "token";
+    // URL constants
+    public static String GITHUB_API_URL = "https://api.github.com";
+    public static String GITHUB_TOKENS_URL = "https://github.com/settings/tokens";
+    public static String GITHUB_API_REPOS_URL = GITHUB_API_URL + "/repos";
+    public static String GITHUB_API_USER_URL = GITHUB_API_URL + "/user";
+    public static String GITHUB_API_USER_REPOS_URL = GITHUB_API_USER_URL + "/repos";
+
+    private GitHubConstants() {
+        // Private constructor to prevent instantiation
+    }
+
+    //String fullURL = GITHUB_API_URL+"/repos/"+repoFullName;
+    public static String getRepoUrl(String repoFullName) {
+        return GITHUB_API_REPOS_URL + "/" + repoFullName;
+    }
+
+    /**
+     * Builds the URL to fetch a repository's forks.
+     *
+     * @param username The GitHub username.
+     * @param repo The repository name.
+     * @return The complete URL for the forks endpoint.
+     */
+    public static String getRepoForksUrl(String username, String repo) {
+        return GITHUB_API_REPOS_URL + "/" + username + "/" + repo + "/forks";
+    }
+
+    /**
+     * Builds the URL to fetch a repository's pull
+     * @param repoOrigen The repository name.
+     * @return The complete URL for the pull requests endpoint.
+     */
+    public static String getRepoPullsUrl(String repoOrigen) {
+        return GITHUB_API_REPOS_URL + "/" + repoOrigen + "/pulls";
+    }
+
+    /**
+     * Builds the URL to fetch a file's content.
+     * @param repoOrigen The repository name.
+     * @param filename The file name.
+     * @return The complete URL for the file content endpoint.
+     */
+    public static String getRepoFileContentUrl(String repoOrigen, String filename) {
+        return GITHUB_API_REPOS_URL + "/" + repoOrigen + "/contents/" + filename;
+    }
+
+    /**
+     * Builds the URL to fetch a user's repositories with optional sorting.
+     * @param sortBy The sorting parameter.
+     * @return The complete URL for the user's repositories endpoint.
+     */
+    public static String getUserReposUrl(String sortBy) {
+        return GITHUB_API_USER_REPOS_URL + "?sort=" + sortBy + "&per_page=100";
+    }
+
+    public static String getUserReposUrl(){
+        return getUserReposUrl("updated");
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 79bf687f8..01977f784 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -128,6 +128,8 @@
     <string name="error_externalstorage_not_writable_hint">Please check if ext. storage is correctly inserted and mounted.</string>
     <string name="error_voicerec_failed">Voice recording has failed</string>
     <string name="error_userlayout_parsing">Error while parsing XML layout file. Please revert to default layout.</string>
+    <string name="error_gh_token_lenght">Token must be 40 characters</string>
+    <string name="error_gh_pr_creation">Error while creating the PR</string>"
 
     <!-- messages -->
     <string name="permission_required">Permission required</string>
@@ -232,6 +234,9 @@
     <string name="github_creating_repository">Creating repository</string>
     <string name="github_no_repository_name">You must specify a repository name</string>
     <string name="error_field_required">You must specify a value for this field</string>
+    <string name="retrieving_repositories">Retrieving repositories...</string>
+    <string name="error_retrieving_repositories">Error retrieving repositories</string>
+    <string name="successfully_retrieved_repositories">Successfully retrieved repositories</string>
     <!-- GitHubConfig -->
     <string name="github_config_btn">Configure</string>
     <string name="github_token_placeholder">GitHub token:</string>