Well that's been beat to death so my short answer is that it's rarely the phone but the network and the carriers gear at play. Remember I'm keeping it short as there are millions of posts on that.
Be careful about Sprint and Verizon models. I've rarely got them to release and move onto other carriers. My advice is unlocked or a model for your carrier.
Then again I have a few BLU models that I got from Amazon for 150 and less that I can pop in ATT, Ting, Tmobile, Rogers and other SIMs and the phone+SMS just works. For data you usually have a few more settings to tinker with.
Here's a shot from my BLU 6.
http://i.imgur.com/XMNgFBl.jpg
I have the LG Optimus L90 with T-mobile that I'm fairly happy with, but the home button in the center is cracked so it doesn't blink for notifications and the GPS doesn't work, so I can't use navigation with the phone.
I know this phone wasn't exactly cutting edge when it came out, so now I'm wondering if it would be better to buy a new phone rather than spend the money fixing it.
The main improvements I'd like to see would be obviously to get the things working that aren't in mine as well as a better camera and call quality. A better screen would also be nice.
I mainly use the phone for actual phone calls, texting, emails, and occasionally navigation, apps like yelp, looking up into on the internet and pictures.
I know this might be a dumb question, but I see a heavily discounted Samsung Galaxy S4 for Verizon. Does that mean it originally worked with Verizon, or that it will only work with that carrier and I can't move my SIM card to that phone?
Any tips on what I should get?

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