CPR Now

*** Revisiting this project because I'm not satisfied with how the app looks and mainly the code behind it. I will be using Angular(2+), Capacitor, and Ionic for learning experience.

Hands-only (chest compression-only) CPR assistant for mobile. Assisting user with audio and visual cues in 2 button presses (3 taps: App open, 'Start CPR Now' from checklist, 'Start' timer). Available for USA/Canada.

Features:

• From app open to start in 3 taps
• Visual and audio cues
• Completely offline
• CPR check list
• Compression depth reminder
• 100-120 CPM setting
• Last 10 start-end time
• Auto sets phone volume so audio cue is heard while giving CPR
• Auto sets phone's volume back to user's volume setting when app is closed or paused

Google Play and the Google Play logo are trademarks of Google LLC.

** Face covering step was added in consideration for COVID

Screenshots/Gif

Frameworks/Libraries used

• .NET
• Xamarin.Essentials
• Xamarin.Forms
• Xamarin.FFImageLoading.Svg.Forms
• Newtonsoft.Json
• Forms9Patch (Auto font size labels)

To Do

• ✔️ Publish on Google Play Store
• 🔲 Publish on iOS App Store

User requirements

Status	UR #	Description
✔️	1	App works offline. No cell/internet service usage after installation.
✔️	2	Language in English
✔️	3	Follow color-related visual impairment guidelines by WCAG, 4.5:1 contrast ratio
✔️	4	14pt font or greater
✔️	5	No quick flashing, seizure inducing, elements. 100 - 120 CPM = 1.67 - 2 Hz which is under 3 Hz and is uncommon to trigger seizure.
✔️	6	A small, compared to screen, flashing/pulsating indicator for BPM. Indicator can not be more than 25% of screen area at typical viewing distances (Mozilla web accessibility).
✔️	7	Image showing placement of hands on chest
✔️	8a	Audio cue for every compression
✔️	8b	Visual cue for every compression
✔️	9a	Ability to start CPM
✔️	9b	Ability to stop CPM
✔️	10	Ability to set BPM between 100-120
✔️	11	Default 100BPM
✔️	12	CPR check list for user
✔️	13	Start CPR button below check list
✔️	14	Timestamp since BPM started for an estimate on when chest compression-only CPR started
✔️	15	Include liability/disclaimer
✔️	16	Auto set volume for audio cue
✔️	17	User can change the 'auto set volume' in settings. Default 80% of device's max.
✔️	18	No advertisements
✔️	19	Free app
✔️	20	Available on Android
🔲	21	Available on iOS
✔️	22	Display reminder of how deep, i.e. 2in./5cm deep or about 2 quarters wide

Testing

Pass/Fail	#	Description
✔️	1	Saves CPM change (100, 105, 110, 115, 120)
✔️	2	Display correct CPM on main page and settings page
✔️	3	Visual and audio cue is ± 3cpm for 1 min using a tap tempo tool
✔️	4	Visual and audio cue is continuously on for 10 min for 100 CPM
✔️	5	CPM metronome starts when start button is pressed
✔️	6	CPM metronome stops when swiped to different page and start-end time is updated
✔️	7	CPM metronome stops when stop button is pressed and start-end time is updated
✔️	8	CPM metronome stops when app is paused and start-end time is updated
✔️	9	CPM metronome stops when app is closed and start-end time is updated
✔️	10	Save start-end time
✔️	11	Display correct start time on main page (same time displayed on phone)
✔️	12	Display the last start-end time as the first entry in history
✔️	13	Display up to 10 most recent start-end time in history in reverse chronological order
✔️	14	Saves auto set volume
✔️	15	Sets auto set volume when CPM metronome is on
✔️	16	Sets volume back to user's original volume level on app pause (app in background but not terminated)
✔️	17	Sets volume back to user's original volume level on app close (app termination)
✔️	18	Start CPR Now button on check list brings user to main page
✔️	19	App works in airplane mode
✔️	20	Disclaimer is displayed in settings page
✔️	21	Disclaimer is displayed on initial app startup requiring user input. If user is disagrees, app closes. If user agrees, disclaimer modal closes and does not appear.

Prototype

Initial thoughts/requirements + sketches/wireframe in /prototype/.