I have a dual sim android phone. I don't think that the make is relevant - I think this is a general Android question, but it's an Ulefone Be Pro 2. It works brilliantly.
One Sim is on Network 3. The other is on O2.
Although I can access 2G/3G/4G on both SIMS, I have to select which sim will be the one used for mobile data. This is not a huge problem, but it would be helpful if one kicked in when the other loses signal.
When you select which SIM is dedicated to mobile data, the other SIM automatically changes its "preferred network type" to 2G and it can't get a signal (including for calls/SMS). If, however, I change the second SIM to the default for mobile data, it can happily pick up 4G. Does this mean that the local network is broadcasting 4G and not 2G?
The preferred network type is greyed out so I can't change it. Also when I go into testing (using *#*#4636#*#*) when I try to change the network type it just doesn't let me.
My questions for you gurus out there are:
1. Is there a way both sims can be turned on for mobile data at the same time?
2. Is it really the case that networks broadcast 4G but not 2G? In other words, am I right that there is signal there to be picked up, I just need to stop 'preferring' 2G?
3. Is there a way I can change the 'preferred network type' to the sim which is NOT dedicated to mobile data?
Thanks in advance for any help