If I bought the game with Steam, can I activate it also in Google play to use it on Android?

@Rennfan Android users can access their files too, just the same as PC players. For me, they're in:

Internal storage\Android\data\com.Jundroo.SimplePlanes\files\AircraftDesigns

It might be different for you, especially if you keep your game files on an SD card, but once you find them you can still use any text editor just the same way.

Thank you!

Can anyone tell me how users create such things on android?

@Rennfan Here lis a link to a REALLY useful bunch of modded sticks you can use if you cant XML mod or are too lazy too

here https://www.simpleplanes.com/a/I5o7vi/modded-fuselage-parts

Anytime

Thanks!!!

@Rennfan here it is, split across a couple of comments. dsr1's help is good to have too, s/he builds cool stuff.

To answer your questions, yes and yes. Good luck, and feel free to ask either of us for help!

Thanks, but I want to try it on my own.
(And thank you for upvote!)

I could do it for you. Resize is easy for me and more powerful engines. Structure panels with wing physics, makes the wing stronger. Angles are also possible here is a link to a build that i helped with.

Thank you for your answer!
If you could link your guide it would be great.
So, that means, if I want to edit the shape in more exact steps than 0.5, I have to use xml or predesigned parts?
And for rotation in more ecactly steps than 90° it is the same?

That's done through xml editing, which is an option on every platform except iOS, I believe. I wrote a guide about it recently which I can link you to if you want to try it, but basically it means editing your plane's save file with a text editor, rather than using the game. If you don't want to do this, or can't, feel free to save components from other planes in your subassemblies, or ask on the forums for a modded part if you need one.