Simple Phone for Seniors

This is a phone app made specifically for old people.
Important: please read this text completely in order to know how to use it!)
For some aged people this is the best way to use a smartphone.
Often, older people cannot handle the features of a smartphone ("what have I done wrong now?"), but they want to see the picture of the person they like to call, and the contacts list can be kept up to date by someone else.
I tried to make the best-effort app:
- all actions are done using high-contrast buttons, no swipe or other actions that are unexpected to the old user- action areas are not near to the frame so it's less likely to touch them by just trying to hold the phone in the hand- jitter is blocked and does not cause multiple actions- large texts- highlighted notice on low battery state or missing connectivity- list of missed calls- date/time screen (closing itself after a while)- reception of SMSes- as far as possible, the hardware keys are disabled against wrong use.
This might better or worse depending on the hardware and Android version, so you might need to put a tape over them (see tip below).- uses google contacts, so the contacts can be managed by someone else (children/grandchildren/...)- this app needs to be installed as launcher!-important: added 'exit' function to launch the phone's settings by pressing the 'volume up' key for 10 seconds (important!)
Please, feedback is valuable and welcome, and Ill do my best to improve.
But suggestions for new features must have serious reasons as the phone must stay SIMPLE!
Tip from our experience: Nexus S with Android 4.1 (up- or downgraded).
Uninstall Google App, Google+, Maps, Hangouts, StreetView and YouTube and some other bloatware: first uninstall the updates, then deactivate them (order is important!).
Using the settings, disable the hardware keys (CyanogenMod makes that easy!) so that they are non-active.
Then there's not much that can go wrong.