There are really three factors to consider when selecting a tripod for dryfire training. Sturdiness, flexibility, and portability. Tripods are typically around the same price (between $20-40) so the choice primarily will depend on what is important to you.
If you plan to implement a more permanent training area in your home, you probably want a very sturdy, heavy duty option that isn't likely to get bounced around if someone bumps into it. For this, you'll probably want a tripod that you'd use for say, a DSLR camera.
If you need your tripod to be very portable, you might consider a tripod that is meant specifically for a mobile phone. These types of tripod are often flimsier and move around when bumped, but you sacrifice sturdiness for increased flexibility and portability.