When it comes to tablets, get a tablet for your daily use, not necessarily just for your photos. It comes down to what you're going to use it for, and what control you want over the way the device functions. The advice I'm giving is from 20 years of being a computer tech, but you still should take it with a grain of salt based on your needs & budget. After all, like any other disclaimer - your mileage may vary.
iPad - simply put - the best at a price. However, you compromise individual customization for performance. Apple controls the entire product line, from the operating system to each component inside the tablet itself. Each app developer knows what the device can do as a result, & tailor their programs according. They can deliver great performance as a result. These don't have a microSD, but a simple adapter fixes this for about $10.
Android tablets - the Swiss Army knife. You have much more control over what you want the tablet to do, but you sacrifice performance in some aspects. Unlike Apple, many manufacturers make Android tablets, using many different components to do so. As a result, app developers must choose more of a "one size fits most" approach to their programming. Most will have a microSD as well.
Windows - the old guard. You can do just about anything you would do on a normal PC, but Windows tablets face the exact same issues that can plague Android tablets - many manufacturers with many different products and the operating system must try to make them all work. Most will come with a microSD as well. The bonus here is that you can connect to your Phantom using the DJI program for your model while out flying.
So, that being said - I use an iPad for photos, an Android S5 for my phone, and a HP Stream 7 for field connectivity. I chose these because I spend tons of time on my tablet, and want the best performance as a result. I want my phone to be free to install apps that Apple wouldn't necessarily allow. Lastly, the Stream 7 lets me change my Phantom settings on the fly away from home. That's just my approach.
However, if you're going to buy 1 device and call it a day - consider the iPad with an adapter if your budget allows. The adapter is a slight pain in the ***, but the performance of the iPad more than makes up for it.