this is on the apps page in the market
**** VERY IMPORTANT!!!! ****
After an update, you must launch Med Minder once to re-register your alarms. Because of this you should NOT enable automatic updates as you may not realize that an update has been applied and you will miss your alert. If the app fails alert you, please launch the app just to ensure the alarms are registered. If you still have a problem, please contact me.
**** ALSO VERY IMPORTANT ****
If you have a task killer, put Med Minder in its ignore list or your alarms may not work!
I would suggest checking your alarms in the app to make sure they are set registered correctly as mentioned above, and if that does not help contact the developer...there is no built in app killer on the Gnex. However if the app is not using memory it will be replaced by an app that needs the memory but that should not prevent the app from working.