This should be how both the iPhone and Android app work at this point (please let us know if this is broken for you on either of those). We still have not fixed this issue on the website, though it is something we plan to do.
Please fix this!
Happens over and over again, in particular as the input keyboard offers both , and . on android.
My suggestion is to treat the most right , or . as the decimal separator and just ignore all others.
var inp = "5.992,30";
inp = inp.replace(/,/g,".");
var parts = inp.split(".");
inp = parts.slice(0,-1).join('') + "." + parts.slice(-1);
For me this would handle all my needs and I'd be happy to get premium for this feature.