Ninja Kiwi is the game developer behind all Bloons games, along with many other games that don't have to do with the Bloons games. They are based in Auckland, New Zealand, but strangely, they still acknowledge American Independence Day, as shown by June Twenty-Ninth's update, giving everyone 
200 to "Celebrate Independence Day", as well as another double MM period. They have been making online games since 2006. Ninja Kiwi started developing games in a spare bedroom with two people working part time. They are currently working in an office with 15 people working full time. When the revamped website went into beta, the website no longer relied on Cookies when logging in into a Ninja Kiwi account. Older designs of the website can be found here.
Ninja Kiwi Blog
The Ninja Kiwi Blog was launched on the Ninja Kiwi website on March 2, 2009 (link to first post). It has been the focal point of game announcements, reviews, updates, etc. ever since launch. Bloons (iPhone/iPod Touch) was the first Bloons game announced on the blog, with Bloons Tower Defense 4 being the first Bloons TD game announced.