オリジナル投稿者： hasjav ,
I downgraded my tarrif in January and have been having battery issues ever since. I recently upgraded because the battery situation got from bad to worse. I had a problem with my new phone so I took it back in-store to cancel my contract. Being without a phone isn't an option as we all know so I put my new SIM in my old phone and I'm wonderstruck because my battery is holding longer... It's actually taking time to charge too which is normal for a HTC m7 one. I don't know why but it seems the SIM was the issue. Network operators send signals to the SIM so I'm sure it affected the battery life especially when service providers want to tie you into a new contract. My contract hasn't been cancelled yet so I'm still on my new tariff in my old phone. Would be interesting to know what will happen when my tariff is reversed... So far I firmly believe it was an issue with the SIM and the network controllers have something to do with it. It's all about business and that's why they're bringing out new phones all the time. Me using my old phone on a cheaper tariff isn't profiting them if you really think of it.