I have a pet "poison" dart frog. She's a beautiful, tiny little thing (~2" at her adult size) and she is actually not poisonous at all. Dart frogs get their skin toxins from eating a diet of ants, termites, small beetles and other small insects found in leaf litter. I only feed her a diet of flightless fruit flies or pin head crickets so she is harmless.
People often think she is just a toy I stuck in my vivarium until they see her jump around. Her vivid colors and small stature makes her surreal. They do not require a lot of space so they would be perfect apartment pets. They are also easy to take care of, make excellent display pets, and are a great conversation piece. You will also have an opportunity to use your gardening skills to create a naturalistic vivarium for your frog to enjoy.