HOW LONG DOES ONLINE NATURALISATION APPLICATION TAKES

It's been 4 months since I went to london for them to check my original documents after applying for naturalisation up till now I've not heard anything..is the paper application better than the online?

There is no paper form it is all done online. The processing time varies between individuals but most will get their decision within 6 months and a few might have to wait much longer as their cases raise complex issues. We cannot advise people on how long an application gonna take. Check the naturalisation timeline post on top of the forum. Posts on application delays will be locked to avoid them going off topic.