I posted this as a comment but I figured it'd be more useful as it's own thread: Hey guys, I've found a way to solve the issue. Though I have very little android development experience, the error seemed like all you had to do was replace any thrustcurve2008 query with a thrustcurve2015 one. So that's what I did, and it fixed it. There are still some other issues with mass components and fin fillets, but with this fix it allows you to run sims. Instructions: 1) Download oponrocket apk from site 2) Decompile with a tool like APK Easy Tool 3) Search file for "openrocket" to find the folder of queries 4) Open all with something like Notepad++ 5) Find and replace all "2008" with "2015" 6) Recompile and put onto phone Let me know if you have any questions.