Firstly, you need to know how much space do you want. If you want something over 32 GB, you're going to use MicroSDXC, wich goes up to 2 TB (128 GB is the maximum you'll find, currently). SDXC needs to be reformated to FAT32 to be supported by smartphones. You may find something about it doing a quick research on Google.
On what comes to manufacturer, this article (http://us.hardware.info/reviews/4544...s-a-difference
) is a good guide, even it's a quite 'old' (1 year) for technology standards. It basically states, after doing some tests, that Sandisk has the best quality, Samsung takes the mid-end front and some good Class 4 even outperforms some low quality Class 10. You may look upon these tests and decide on what one will fullfill your needs.
For me, a Samsung 32 GB UHS-1 would be fine. It's very fast (UHS-1 is faster than Class 10) and made by a good manufacturer. It may not be a Sandisk, but isn't so far from, anyway. Plus, we're talking about smartphone storage, which usually won't require anything so high end, like professional photographers usually do.