My simplest go to Stylus for drawing is a basic Merkury Stylus, the purple Stylus in the photo. It is inexpensive and allows me to mindmap, my main use of a stylus on my iPad. I take notes during meetings or presentations as mindmaps. My favourite app for mindmapping is Notability.
For students who have trouble with touch features I really like the Cosmonaut Stylus by Studio Neat. It is thick and about the size of a whiteboard marker. It has a rubber grip and is very smooth on the screen. I really like it, and at only $25 it is especially good for our young learners.
The third stylus isn’t for tablets, but is an extra big Nintendo DS pen. The Nintendo DS just needs a basic plastic stylus, and the default styluses are very thin and hard to handle for some learners, especially young ones with a project like Nintendogs. The pencil stylus came with the game Scribblenauts, but a similar stylus for the Nintendo could be created and it just has to be plastic without any wires or metal in it.
Touch screens are a fabulous technology, but some users need a pen type stylus for different functions. There are good options out there to support our learners.