From my many searches, all I read is that newer phones have code to keep them from overcharging. My android razar maxx is plugged in 24/7 because all I use it for is tethering. After a year or so of doing this, I realized my razar is now fat because the battery has become fat from constant charging. Although the phone works fine and the battery appears to have its original life, will this eventually ruin my battery and/or my phone? Is there an application to prevent overcharging? If not, at what percentage drain should I start charging?