There are a few gyms that let you cancel online. If you know of any other chains that require certified mail/hard to cancel requirements let me know. I recently had to add a signature feature to my app for Retro Fitness!

# Require certified mail (100% sure on these)

- LA Fitness

- Planet Fitness

- Gold's Gym

- Retro Fitness

# Let you cancel online / do not require in person or certified mail (From memory based on my research)

- Orange Theory Fitness

- Blink Fitness

- Equinox

- 24 hour fitness

(edit: formatting, clarification)