Started with J2ME, then BlackBerry, moved on to iOS, followed by Android, jumped on to the AngularJS single page web app (buzzword HTML5) ship and now working with Android again (woohoo).

Languages I know (in order of decreasing knowledge): Java, JavaScript, Obj-C, C/C++, Python, Ruby, bash scripts, Swift, Groovy.

DBMSs I know (as in I used them at least once): SQLite, PostgreSQL, MySQL, Microsoft SQL Server.

OS preference: Linux (Mint), OS X, Windows