Hi - I am new to this forum and it seems like it may be a good place to ask this question.

I have a 9 year old boy that uses a phone to speak. He has autism and is non verbal. He uses an android (or iOS) text to speech app that allows him to type a word/phrase/question and hit a speak button that then reads the text so people around him can converse with him. It is his sole source of communications so it is critical that he have a reliable phone that lasts the day without needing a recharge. He is also a 9 year old with perhaps a more than average rate of dropping phones and getting them wet etc. He also is not as careful as you or I would be at pulling out a charging cable and has damaged USB ports (and cables for that matter).

This phone does not have to do ANYTHING beyond running this one text to speech app and a gps tracker I have for safety purposes. He does not use the camera or make calls or play games on it. He has other devices that are for games and education - this is dedicated to the speech app.

What we have tried so far:
We have tried iPhones and iPod touch devices but the battery does not last and they seem to break easily. While I like apple devices, they are very expensive and the battery seems to lose life very quickly.

BLU studio energy. We have been using these for about 6 months now.
Pros:
The battery lasts longer than anything - we can go almost 2 days between charges if needed.
The screen size is nice and when the phone is not broken it is a very nice piece of hardware.
Cases are not very good and there are not many available - we need one that protect it from drops, is difficult to remove (otherwise he takes it out of the case) and will accept a lanyard so he can hang the phone from his neck - he uses it every few minutes and this is really the only way we can make it available enough.
The price is good for a phone with these specs - especially the battery - it is about $150 from Amazon. We use T-mobile so I just plug in a sim card from them.


Cons:
USB port is very delicate - they won't charge after a while due to this.
Screen starts getting vertical lines on it and wide bands of off coloring - it could be the brightness is not correct on part of the screen. For our purposes this is not a show stopper and he can still use the app but it is not good for long after this.
One of them decided to suddenly stop turning on.
Unfortunately, they are very prone to breakage and require warranty replacement a lot.
The customer service from BLU products is very poor - we bought two of these so we would always have a spare and so far we have had one on the way to or from BLU products for warranty repair or replacement at all times over the last two months. The seem to get unresponsive and when you call them to see if your phone has shipped they say it has not and offer no reason or excuse as to why it is beyond their ridiculous 15 day turn around time.
They ship it on the slow boat from Florida to where we are (California) so it takes a week to get it in our hands once they finally ship it.

So a phone that has a large battery, is durable and has a lot of case options are the main requirements. Inexpensive is also important as we will need to buy two so he has at least one spare.