This app was mentioned in 14 comments, with an average of 1.43 upvotes
Solved! Tentacle Wars, not a white background as i said. https://play.google.com/store/apps/details?id=com.fdgentertainment.tentaclewars.gp.free
Posted this in another thread. It's not a medieval-type thing, but the concept is similar. You'd probably enjoy it. Since I last played it, apparently it has a "random level" mode now, too!
https://play.google.com/store/apps/details?id=com.fdgentertainment.tentaclewars.gp.free&hl=en_US
Not sure if it's on the App Store.
If you like the expedition game, I'm pretty sure you'll like this game:
https://play.google.com/store/apps/details?id=com.fdgentertainment.tentaclewars.gp.free&hl=en_US
Tentacle Wars was really nice but short.
Osmos was also pretty amazing.
sounds an awful lot like tentacle wars, but I don't think that what you're looking for. (also available for android)
Tentacle Wars feels pretty similar to me so you may enjoy that one.
I love these kinds of games, and I use them on my phone a lot to kill time. I've got a couple to recommend, if you're interested.
Tentacle Wars is my personal favourite, and I highly recommend it. The levels get really tough near the end, and it took me awhile to catch on to many of the tricks you can do. Google Play and iOS.
Auralux is like a far slower Phage Wars. It advertises itself as a sort of pure strategy game where you send your units to capture stars, which will produce more units. There are no special stars which give production or defensive bonuses or anything like that, and every unit moves at the same speed. Strategy plays a larger role than reflexes because of the slow speed at which all the units move. You need to think carefully about when it's worthwhile to spread your forces out. The PC version has similar controls to the mobile version, so it can take some getting used to. Google Play, iOS, and PC Browser.
Auralux: Constellations a faster-paced sequel, which plays a lot like Phage Wars 2. There are a lot of unique maps, and it has an online multiplayer. Google Play, iOS, and Steam.
There's also Rapture, where you play as a God to help your followers take over the world. As well as commanding your units directly, you can impact the world with Acts of God. If an enemy is getting a foothold on a continent that you want, you can cause a plague to soften him up. By the time it's over, his production will be far worse. There's also a system for specializing in either military, production, or faith. You can change your focus anytime, so you might use a faith focus so you can afford to summon some tornadoes on an enemy, then change to a military focus to take advantage of his depleted forces, and finally use the production focus to repair the land faster once you've taken it. Google Play and iOS.
Hope you find something you enjoy!
Try Tentacle Wars or where it startet Tentacle Wars though flash is dead, there is also a second flash part The purple menace
You'd probably like tentacle wars https://play.google.com/store/apps/details?id=com.fdgentertainment.tentaclewars.gp.free