This is a talking altitmeter for Android phones (Android 4+). It is designed for minimalist fliers of hand-gliders, paragliders and untralights. Simply set the altimeter datum and turn off your phone. The app continues to talk your height and/or groundspeed even though the phone is in standby mode.

It speaks your current altitude/groundspeed at user-specified intevals using your phone's realistic text-to-voice feature.
Talking AltimeterTalking Altimeter
See 'setting it up', below, for details on how to install the app and your text-to-speech phone feature.
FREE Pilot's Talking Altimeter for Android
There are settings allowing you to customise the altimeter including setting the altimeter to read from sea-level or take-off/runway height and using imperial or metric units.

You can save your battery power for after flight by choosing a battery percentage at which the app closes.
Download the latest app APK installer.
Setting it up...
TalkAltimeter 1.0
Setting it up...