Non-stop crashes since it was installed by the SIM card. Doesn't matter that I've never actually launched the app myself. Just runs in the background, spamming "Unfortunately, T-Mobile has crashed" until I manage to be quick enough to force stop the app. Only solution offered by T-Mobile is: buy a new phone. Sorry, but I'd rather have Sprint back. They may have gone downhill in customer service in recent years, but they didn't try to shove upgrades down my throat and never screwed up the phone.