[Other SmartWatches] danesaia:
Here's how to get 3G Cellular Data and Phone Calls Working

Ok everyone...I haven't seen too much information on this subject so I thought I would provide what I know at this point. What I have found through my trials and troubleshooting:

Taking into consideration I am in the United States and in a fairly suburban area.

What I tested and found:

1. Lycamobile - a T-Mobile MVNO, they have good plans and was easy to setup. I opted for the $19 plan. The 3in1 sim only cost me $.01 from Amazon. Once installed the D5 seemed to keep trying to connect to T-Mobile towers, so much so that I would check the "About Device" under "Settings" and look at "Mobile Network" and I would get random connections with good signal and connected mobile network. But as soon as I would make a call, everything would drop out. After about a day of messing with the apn settings and such I gave up.

2. Next I thought, well I am Project Fi member, I'll try a data only sim and see how that works. That was worse than the above. So I gave up on that. (Keeping in mind that Project Fi Data Only sim's only work off of T-Mobile towers, unlike their full sim that works of both T-Mobile and AT&T). So I scraped that idea.

3. I decided to post in this forum for any help, low and behold one person responded, thank you [MENTION=772301]hideffer[/MENTION] for your help, that he used H20 Wireless with plug and play results. I looked H20 up and found they use AT&T towers. Found this interesting so I thought I would give it a try. I went down to my local Boost Mobile store and asked them if they could sell me a H20 mobile 3 in 1 sim (you will need a nano sim for the watch). After some hesitation, and checking with his boss he sold me one for $10.00 (note: you can get this free on H20 site or on Amazon for like $.03 but I am impatient and wanted to try it right away). So I paid went home, registered on H20 site, picked my plan (Unlimited Talk, Text, and Data first 500MB LTE speed and after is 128Kbps for $30 with auto renew) popped the sim card in and BAM it worked. No configuration, no apn messing around.

So now I can literally make phone calls from my D5, get text's through Hangouts or whatever you choose etc.

I am so thoroughly impressed by this watch for the cost. I did so much research on smartwatches, and I don't understand why these watches are not more prominent. I can go anywhere now with just my watch. ZIt runs full Android, which means I can basically load or use any app. Sure there are some slight limitations...yes it's small and the keyboard is somewhat a pain...thank goodness for Google Voice. Seriously, I have Phone, Text, GPS (works great), Health...the only one thing that could possibly make this watch any better --> ok a few things are a camera and swappable watch bands and a bit more memory would be nice. For me these are not deal breakers, cause honestly, the band doesn't bother me. As for the camera, that's what my DSLR is for, and most likely, for now, I'll have my phone with me. I know the AWatch has a camera but at double the cost not worth it to me. And I am sure by the end of the year the makers of the D5 and such will have a camera on these at around the same price point...so I'll wait. Memory, just be sure to move any apps you can to the RAM from the ROM and you should be ok.

That's all for now, if you have any questions feel free to ask, I am not a programmer but I am very good with troubleshooting and working out things and would be glad to help if I can. Have fun!!!