Most smartphones these days have an LED flash beside the camera lens, but, after several years in the doghouse, Xenon lights are starting to make a comeback. Most folks tend to not notice the distinction, but it can be an important one, leading to a huge difference in the quality of flash photography.
Turning your phone in to a WiFi hotspot can be incredibly useful. Pushing wireless to a tablet from a phone is much cheaper than forking out for a second data plan.