Basically any phablet/smartphone with a larger screen is ideal (makes it much easier to use the phone for uptodate/medscape/google consulting etc) Any iphone before the iphone 6 is simply too small to be useful for web browsing. I used to have an iphone 4 and barely used it for anything except texting and making phone calls because the screen was too small and clumsy when trying to navigate the web or text based medical apps. I am currently using an LG G3 and absolutely love it. Some people suggest iPads, but honestly these can be pretty inconvient sometimes because they are too large to fit in most pockets. You will inevitably set it down at some point and forget about it and it will disappear. I'd recommend a phone with a 5.5+" screen, still small enough to easily fit in your white coat or pants pocket unlike a tablet, but large enough to make reading and web navigating on the fly a breeze.
