This app was mentioned in 40 comments, with an average of 2.38 upvotes
Lots of Android people from the s4gru.com forums use Signal Check Pro (it was developed by a user over there).
https://play.google.com/store/apps/details?id=com.blueline.signalcheck&hl=en
There's also a Lite version.
https://play.google.com/store/apps/details?id=com.blueline.signalchecklite&hl=en
The following app was initially designed and developed for the denizens of s4gru.com, a Sprint fan site. It moved on to being a paid app but since the members of that site are either network engineers/theorists and/or students/work in the industry I understand the app has a good reputation.
Signal Check Pro.
https://play.google.com/store/apps/details?id=com.blueline.signalcheck&hl=en
I'm not familiar with an official method but I use signal check pro https://play.google.com/store/apps/details?id=com.blueline.signalcheck . The problem is with the signal. You may be in a band 12 area but band 2 or 4 is preferred due to typical speeds. Band 12 is to fill in the cracks and to penetrate objects like walls. So you may not easily see band 12/700mhz until you're in specific areas.
I knew I had it before the app due to actually getting service in the back of a grocery store or in my office conference room. Where others have no or poor service I have full LTE in many places. YMMV of course but over the past 16 months or so it's been a huge change.
My favorite is Signal Check Pro: https://play.google.com/store/apps/details?id=com.blueline.signalcheck&hl=en
It now supports accurate results on Android Nougat on most devices (including Nexus 5X). I like the status bar notification.
https://play.google.com/store/apps/details?id=com.blueline.signalcheck
There is also an older SCP lite edition that is free and not as updated. The app developer is working on bridging them together.
Basically download the app and then open it and take a screenshot of the info that's shown.
An update to SignalCheck was pushed out yesterday; it includes the changes that should resolve the issue you were seeing. If you have any more issues please send an e-mail.. I'm not on Reddit very often.
I have been using for the last 3 years. I have not had any major problems. Here in the upstate your phone will mostly be on tmobile network with good speeds. This app will show which network you are on, https://play.google.com/store/apps/details?id=com.blueline.signalcheck
Yeah, I'm using SignalCheck Pro so I know I was on T-Mobile LTE https://play.google.com/store/apps/details?id=com.blueline.signalcheck
Will have to try that tomorrow when I know someone with TMUS PostPaid will be over. I know in general, that TMUS in Chicago is not the best of the carriers due to limited LTE spectrum. I'm expecting Chicago coverage and speeds will vastly improve when they can roll out the 700MHz A-block spectrum they acquired from AT&T back in May. That will still likely be several months out. http://www.rcrwireless.com/20160525/carriers/t-mobile-pockets-chicago-700-mhz-license-att-leap-subsidiary-tag2
I mean the idea is neat, but does it really matter what carrier you're on if the system is working? There are apps to check what service you're connected to if you're really that curious.
You can probably use one of those network signal checking apps to notify you whenever the signal is lost. I know SignalCheck Pro can do this, but there may be other free apps that can, too.
I use Signal Check Pro, not for strength but just to see bands. However, it has a Neighbor Cells section that shows dB strength in parentheses. I don't know if the free version has it though. https://play.google.com/store/apps/details?id=com.blueline.signalcheck
Ugh, it helps to get the right MCC-MNC. 312-250, not 312-530. You're right, it does say that. I'm a dope. Thank for correcting me on that.
SCP = Signal Checker Pro. SCP does report the 312-250 MCC-MNC when it connects to a Sprint Keep when using my Pixel 2XL on a T-Mobile SIM. CM does not. I also have LTE-Only enabled or it would never connect to any Keep site and drop down to 3G/2G or no service.
I can't recommend Signalcheck Pro enough! https://play.google.com/store/apps/details?id=com.blueline.signalcheck
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Turn off all of the alerts. I have it set to give me a constant notification at the top that shows I'm on LTE, which band, and what my signal strength is. It's a small notification icon showing all this info. Lets me know which band I'm on when I'm experiencing problems.
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My S10 Plus is getting terrible Band 41 data in my area, though in New Orleans last week I was pulling 104mbps down, 35mbps up! Right now I'm on band 25 getting 5/2.
I'd highly suggest Signal Check Pro (https://play.google.com/store/apps/details?id=com.blueline.signalcheck). It's cheap and works very well. Plus, it's a low overhead app that allows a lot of customization (like the always persistent notification that can be turned off and on).
Many of us have collected extensive information about your network infrastructure (as well as your competition) using apps which can record engineering diagnostic information (such as SignalCheck, CellMapper, and Network Signal Guru). Have you ever considered allowing network enthusiasts to act as ambassadors to your network engineering team to help collect real-world performance data and to help diagnose network issues?
I have the direct phone number to the advanced tech support team in Oklahoma City, but even they are not equipped to handle some of the advanced issues some of us have called about in the past. For instance, I've been tracking an LTE handoff issue with a local Sprint site in which the network is actually sending my phone an RRC Connection Release packet and pushing it down to 3G even though I have a strong LTE connection. Your tech support team can't adequately address this issue because they are required to fit it into an arbitrary problem category (e.g. unable to use data).
Quite a few of us would be willing to carry an extra phone loaded up with diagnostic apps and collect engineering data for you, especially if it meant having a more direct line of contact with your engineering team.
I use Signal Check Pro. There's also a free Lite version. Network Cell Info is another good one also with a free Lite version.
Looks to me like Signalcheck Pro.
I've been using SIgnalCheck Pro to see which network I'm on: https://play.google.com/store/apps/details?id=com.blueline.signalcheck&hl=en
This app is very useful at providing information on the correct carrier when Signal Spy/ Fi Switch/whatever just isn't doing it. Even though Signal Spy showed just T-Mobile, it has shown me the actual carrier when abroad. There is a free version which I think has the same ability as well.
It should be noted, though, that one of the developers of Signal Spy, /u/dmziggy, has hinted that this feature is coming to the app soon, so perhaps when that happens having this second app will be redundant and obsolete. I guess we'll see.
You could try SignalCheck Pro.
https://play.google.com/store/apps/details?id=com.blueline.signalcheck&hl=en
Got you covered! s4gru.com denizens use this all the time. One of their users develops it.
https://play.google.com/store/apps/details?id=com.blueline.signalcheck&hl=en
I use signal check pro.
https://play.google.com/store/apps/details?id=com.blueline.signalcheck
They also have a lite version if you do not care to spend money.
https://play.google.com/store/apps/details?id=com.blueline.signalcheck There is also a lite version which is free
If you want to force carrier there's some dialer codes available at: http://forum.xda-developers.com/nexus-6/general/project-fi-fi-dialer-codes-to-force-t3132393
Program that I use to check carriers is: https://play.google.com/store/apps/details?id=com.blueline.signalcheck&hl=en
They also have a lite version(I don't use this one): https://play.google.com/store/apps/details?id=com.blueline.signalchecklite&hl=en
Just use SignalCheck Pro. Great persistent notification with customization. I use it to report the band number. There's a free "lite" version, too, that just doesn't have a persistent notification.
Edit: Oops, missed the iPhone part! But seriously, still an option! Switch to Android and install the app! Haha