There is no denying that real-time strategy games are a hard nut to crack on mobile devices. It's tough to fit all of the intricate play mechanics, complicated strategy, and extensive storyline into a touchscreen. Planets Defense does a great job of making the controls work for high-speed gameplay and micro-management, but it still isn't quite a fully realized strategy experience. All things considered, it's still lot of fun and one of the best efforts I've seen.
Imagine mixing together the artistic style and baser strategies of StarCraft with the simple command and combat of Galaxy Empire. As you might have guessed, the result is very familiar - it has been done several times in the past. However, Planets Defense improves on this formula by balancing management of individual unit activity with the need to automate some of the more mundane operations.
Your time will be split pretty evenly between two perspectives: the on-planet base builder, and the solar system battle view. Planets are operational centers for collecting resources and building combat ships, all of which is accomplished through erecting buildings for production and defense. Since planets are limited in the number of facilities they can support, there is a balancing act between collecting raw materials and preparing for war.
Combat is very fluid, basically relying only on the player to direct ships toward orbital body to either guard it or shoot it. Ship-to-ship fire is managed entirely by the AI, but there is little need for detailed control. Most battles are really just about letting the missiles fly. Obviously, this is pretty simple compared to proper RTS games, and it does lack some of the grandiose flair and intensity that can only be had with truly epic battles. Half of the fun for this genre comes from frantically clicking or getting into the zone where every single action is performed with elegant precision. While this game isn't going to give you the same thrill, managing base and ship construction in concert with very frequent attacks will definitely keep you on your toes.
Between levels, you can perform technology upgrades with "energy sources" collected during missions. This in-game currency seems to be moderately slow flowing and mostly random, but levels can be replayed to grind out a bit more if necessary. There is another element of gameplay that is absolutely vital to success and pretty uncommon in this genre, all of your unspent resources carry forward from one battle to the next. Because of this dynamic, revisiting easier missions to build up a cache becomes a legitimate component to conquering some of the higher levels.
With all of this talk about resources and rare currency, you might expect in-app purchases to be crawling about. Believe it or not, there isn't a single IAP to be found. Unfortunately, there is no multiplayer and the full game isn't extremely long at 25 missions, but it's still very worth the price at only $1.98. There is also a free demo available with a tutorial and the first 2 levels, which I strongly recommend for testing on your device; I had a really bad issue with touch targets on my Nexus 7 that didn't appear on my HTC One. Despite a few issues, I really enjoyed Planets Defense and I would definitely call it a must-have if you even remotely enjoy real-time strategy.