[Nexus 4 Q&A, Help & Troubleshooting] dbarajas1401:
I want to know if there is anyone else with the same problem as myself to try and troubleshoot, identify, and hopefully fix the following problem:

History:

I had an unlocked Nexus 4 on Straighttalk (on ATT's network by swapping out the sim from the nokia e5) from Feb. 2013- Dec. 2013 and had no problems with data or sync. In late December of 2013 I saw that Straighttalk was selling ATT micro sims again with 4G LTE compatibility so I decided to buy one (even though 4G LTE is not on the Nexus 4 without root) just in case I ever decided to upgrade phones. I activated the sim, updated the APN settings, and all data, mms, sms, and phone calls were working.

Problem:

Data was working (tested by using the browser and Facebook), but there were sync issues with all my google apps: gmail, keep, calendar, browser, etc. After a month of troublshooting, I've figured out that I get intermittent data signals, which is causing my google services to not sync properly. I have narrowed it down to a couple of things that are possibly causing the intermittent data:

1) The new APN from Straighttalk is not working properly for non-4G LTE phones

2) The new APN settings don't allow background data

3) The new sim card doesn't work properly with my phone

Solutions That I've Already Tried, and They Didn't Work:

- Tried every possible APN setting on the XDA Developers forums and the internet

- Tried using the "old" apn settings

- Tried using ATT's apn settings

- Factory reset

- Flashed .48 radio

- Tried to CM11 with the newest radios, older radios, and hybrid radios that enable 4G LTE

- Unroot, locked bootloader, and flashed factory image downloaded from the Google developer's website

A couple of other notes:

- I tried activating a Tmobile micro sim to test if it were my phone, but everything worked perfectly with Tmobile so I know it isn't the phone (I wish I had tried this before factory resetting, rooting, and going back). If I switched to the Tmobile sim, all my problems would be fixed, but my biggest problem is that the reception for phone calls was horrible so I want to stay on ATT's network

- When I turn airplane mode on and then off, all my data syncs properly. But who wants to manually sync every time they unlock their phone? At my job replying to emails in a timely manner is extremely important so my data not syncing properly is not ideal.

- Sometimes when I unlock my phone, the data tile in the swipe down menu is orange. Indicating a bad connection

- All my phone calls, sms, and mms work fine

- When I unlock my phone and open the web browser, it sometimes takes a while to start loading the web page. Similarly, when I manually load my email (in the gmail app by swiping down) it takes longer than normal.

- When I send an email, it takes a while to actually send

- With this new ATT micro sim, the network is no longer called "Home" (like it was with the other sim), it now has "AT&T". I'm guessing this has something to do with me not being able to switch back to the old APN settings.

My current APN Settings are:

Name: Straighttalk ATT

apn: tfdata

Port: 80

MMSC: (insert new straighttalk mmsc, I'm not allowed to post urls and this is a url I guess)

MMS proxy: 66.209.11.33

MMS Port: 80

APN Type: default,supl,mms,admin,internet,hipri

I'm running android 4.4.2 with the .98 radio, or in other words simply stock android.

Ookla Speedtest: 5.25/1.13 mbps and 160ms ping. It does lag when doing the upload portion of the test (i don't know if that's significant)

And everything else is left on default. If there is anyone else with the same problem let me know and I'd be glad to troubleshoot and if there is anyone that would like to help me with troubleshooting it would be greatly appreciated. Thanks.