[myTouch 4G Q&A, Help & Troubleshooting] shlongwoodian:
Location, Mobile Networks, GSM vs WCDMA, etc.

I was about to post a new topic on this, but the nifty little Ajax monkey robot showed me this thread matched my keywords.

So I'm one of those d-bags that uses Facebook Places (Check-in). Not a lot and I don't frickin' check-in everywhere I go. I hate it when people do that. (Thanks for letting all of Facebook know you're not at home, so we can go break-in to your house.) I do use it though, as well as Yelp.

While I'm out, I'll go to check-in and it just spins its wheels - i.e. no Places load. I can be outside, clear sky and have GPS enabled and it still can't find my location. I noticed the same with Yelp, but Yelp actually errors out and tells me it cannot determine my location and prompts to go to my Location settings. Even with GPS enabled, Yelp still cannot determine my location. I noticed this here in Orlando/Longwood, FL and all the way down and through Ft. Lauderdale.

Obviously, if I enable WiFi my location can be determined instantly - e.g. Facebook Places finds it, Yelp finds it, etc. I'm not on WiFi all the time, so I don't really want to only be able to check-in at home.

I checked my APN and it has't been touched, it's at the default. I am on Ice Glacier, so I was willing to believe something could be different, but APN is correct. I also checked my stock ROM (Nandroid backup) AND my fiancee's phone, which is running stock (rooted).

I'm thinking it's got to be something to do with how my/our device(s) are registered on the network. So I look at the Network Mode and notice the default on my/my fiancee's phone is GSM/WCDMA Auto.

Just for giggles, I decided to knock it down to GSM Only. The radio restarts and then no H comes back - only Edge. I'm not just talking about the icon, I'm talking about the actual speed. Here's the cool part - once I went down to Edge (forced by being on GSM Only), guess what? Locations work perfectly now. ;) Albeit a bit slower, but Facebook Places loads Check-ins immediately and Yelp is able to find my location now.

If I switch back to the original setting, the radio restarts, I get H back and for anywhere between a few minutes to a few hours, my location can be found. After a bit of time, I'm back to the same boat - location cannot be determined by mobile network.

I tried this on my ROM, my stock ROM and my fiancee's MT4G running stock - I can reproduce this 100% of the time.

I figured next, I'd try WCDMA Only...

To my surprise, location works perfectly now, 100% of the time. I switched to WCDMA Only last night and I have been able to use any/all apps that determine location by mobile network.

I will record a video of this, as again, it is 100% reproducible on multiple MT4G's and various ROMs. Our signal strength and network speeds in this area are amazing (Orlando/Longwood, FL). I consistently get 7-9 mbps down and never go below 6. My battery life is fantastic, as my radio is never switching between network types (note: In other cities, like in south Florida, battery can die super quickly because it's constantly jumping from Edge to H and back again).

Even better, when I use the Speedtest app, my server list no longer only has Atlanta or Washington, D.C. as my closest servers. I now have a ton of servers here in Florida, out by the coast, etc.

So there's my brain dump for now. I am not saying I have a fix, but I am saying there is definitely an issue w/ how these devices are registered on the network. I'm not saying I should be on WCDMA Only either, but I can say that in our area, my connection is perfect and now I have no issues with location via mobile network.

What the heck could the issue be? Why wouldn't the device be able to be found on the network when on GSM/WCDMA Auto? Edge does location flawlessly (when forced via GSM Only) and WCDMA Only does location flawlessly as well.

I'll do my best to record the video this weekend and show this top to bottom, but I figured I'd share what I could to see if A) this would help anyone with this issue and B) to see if anyone could shed any light on all of this.