Originally Posted by
richarddd
Oddly, it's 3.8/5 on the google play store. In any event, I installed it for the 500mb free. The app has been easy to use. It appears to work so far, .
I have been using BNESim for backup data. It also roams on AT&T and TMO in the US, although it appears to prefer TMO. It generally works fine, but there are some areas it doesn't work, even though other providers that use one or both of those networks do work. This puzzles me.
What probably occurs with your roaming dropouts is, AT&T and T-Mobile probably have roaming agreements with local carriers if they don't cover those areas. The MVNO's do not get the benefit of those local roaming deals (Because $$$), so the primary carrier loses service. I have seen this happen and it is a commonly reported issue on cellular forums.