Like millions of you, I have downloaded, enjoyed and even finished all the levels of Angry Birds, at least so far... more levels, please! So what is a user to do? Sure, Chillingo (which EA is buying) has released another Angry Birds version for Halloween and you should definitely get that. And they also released Cut the Rope, another pick-up-and-play game with cute graphics. But it's not the same in terms of controls or even orientation (landscape versus portrait). Fortunately, with any successful app, there are other vendors stepping up to the plate.
I have enjoyed two such apps lately, specifically Fragger from Miniclip.com and Cannon Cadets from XMG Studios. Both apps are more "militaristic" in their themes, with Fragger relying on throwing grenades at aliens or terrorists whereas Cannon Cadets has you launch "soldiers" into structures. With Angry Birds I never had to worry about age or gender appropriateness, but you might want to check out the free version of Fragger or the screen shots of Cannon Cadets before you buy.
Fragger is an iPhone app that scales well on an iPad. While a Universal app is always appreciated, the attention to detail makes Fragger enjoyable on the big screen.
Cannon Cadets is a Universal app so iPad owners get to benefit from the larger screen. And the developer has really paid attention to detail with Cannon Cadets. The background scenes are beautiful. My only recommendation would be to make the cadets larger or give them more personality, the way Angry Birds does. Perhaps some animated "cut scenes" would help, between missions.
As mentioned, Fragger has a free version and the paid iPhone app is just $0.99. Cannon Cadets is not free but at $0.99 for a Universal app, it's a great deal. Considering Angry Birds HD for the iPad is $4.99 and doesn't really add much, I appreciate XMG's pricing strategy. I've finished all of the levels on these games as well, but more levels are expected and Cannon Cadets actually adds a Level Builder where users can create and share levels with other players.
Developers often ask my advice about building apps and I usually tell them to avoid copying other successful apps unless you can "create a better mousetrap". In this case, these apps improve on the genre that Angry Birds has "owned" so it's worth owning these apps!