Angry Birds Transformers generated characters to assist in a level for a limited time. Coins may be collected either during runs, popping pigs and/or simply by waiting and collecting coins that generate over time from freed areas. Some levels or features can be only unlocked when the player has upgraded enough Transformers to level 15. The game is the fourth game in the franchise to be compatible with Angry Birds' Telepods, a toy line that is also used in other "Angry Birds" games such as: "Angry Birds Star Wars II", "Angry Birds Go", and "Angry Birds Stella". When using Telepods, it can summon
Angry Birds (video game) device, and Apple's iPhone and iPod Touch mobile digital devices, Rovio has released versions of "Angry Birds" for additional devices. An iPad-exclusive version, "Angry Birds HD", was released with the iPad mobile digital device in April 2010. In August 2010, "Angry Birds" was made available to the Palm Pre phone running Palm's webOS operating system through its App Catalog online store. Symbian^3 phones received a version of the game in October 2010, which initially includes only the "Poached Eggs" and "Mighty Hoax" episodes. Angry Birds works on Kindle Fire and Kindle Fire HD. In May 2010, Rovio announced plans for