diff --git a/hyperstream/tools/apply/2017-11-27_v0.0.3.py b/hyperstream/tools/apply/2017-11-27_v0.0.3.py
new file mode 100644
index 00000000..8c4e587c
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+++ b/hyperstream/tools/apply/2017-11-27_v0.0.3.py
@@ -0,0 +1,38 @@
+# The MIT License (MIT) # Copyright (c) 2014-2017 University of Bristol
+#
+#  Permission is hereby granted, free of charge, to any person obtaining a copy
+#  of this software and associated documentation files (the "Software"), to deal
+#  in the Software without restriction, including without limitation the rights
+#  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+#  copies of the Software, and to permit persons to whom the Software is
+#  furnished to do so, subject to the following conditions:
+#
+#  The above copyright notice and this permission notice shall be included in all
+#  copies or substantial portions of the Software.
+#
+#  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+#  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+#  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+#  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+#  DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+#  OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
+#  OR OTHER DEALINGS IN THE SOFTWARE.
+
+from hyperstream.stream import StreamInstance
+from hyperstream.tool import Tool, check_input_stream_count
+
+
+class Apply(Tool):
+    """
+    Simple tool that applies a function to every data item
+    """
+    def __init__(self, func, include_timestamps=False):
+        super(Apply, self).__init__(func=func, include_timestamps=include_timestamps)
+
+    @check_input_stream_count(1)
+    def _execute(self, sources, alignment_stream, interval):
+        for t, d in sources[0].window(interval, force_calculation=True):
+            if self.include_timestamps:
+                yield StreamInstance(t, self.func(t, d))
+            else:
+                yield StreamInstance(t, self.func(d))