The Lil Monkey dome climber is 24.80" L x 66.9" W x 46.5" H -- the perfect size to be big enough to have fun climbing but not big enough to get hurt if M2 falls off. It's only about 14lbs., too, so I can easily move it around the yard. The grass hasn't been damaged by it either, since the weight isn't substantial. The climber works for indoor play as well when winter arrives in a few months. The structure is very sturdy even though it's light. A had no problems putting it together.
You can set up an app on your mobile device for kids to interact with, though they have to be standing away from the climber to do it. It can't be used while the kids are climbing or playing with the set. M2 hasn't had any interest in the app, she just wants to climb! Honestly, I think the climber is best without the app. There just isn't any need for it and it actually detracts from encouraging the kids to move around.
Kids up to age 6 can use the play set. M2 has no problems climbing around the whole thing and it's never so much as wobbled. Older kids may need the climber to be anchored to the ground so it doesn't pop up or tip over. It's a great toy to get kids active. I'm sure baby B is going to have a ball with the Lil Monkey, too, once he's big enough to join in.