It's pretty common knowledge that using strong passwords is important, but we'd can understand it if you sometimes take shortcuts for the sake of convenience. A great example for many of us would be with our PCs. Given the fact that we login to them all of the time, it can get old typing in (or even trying to remember) your secure password. That's where decisions need to be made: do you use a strong password, or a weaker one to make life easier?
Hold that thought, because Microsoft has just come in with a third option: use a strong password and make life easier.
With its just-released "Phone Sign-in Beta" for Windows 10 Mobile, Microsoft gives users the ability to log into their Windows 10 devices (desktop, notebook, et cetera) with nothing more than this app. You'll of course need to first pair the phone with the PC, but from that point on, you can simply load the app up when you are in the proximity of the PC, and then click on its name to unlock it.
The obvious question is: when on Earth are Android and iOS users going to get this functionality? Well, as the current app is WM10-exclusive and is being considered a beta, we can hope that Microsoft will follow-up with alternative versions as soon as this one comes out of beta (or even before, if we're lucky). It's a waiting game at this point to see if it will happen.
In the meantime, you can continue using a strong password with your PC, or create a PIN code, which Microsoft insists is more secure than a written password. If you insist on the Bluetooth method (and we can't blame you), there do exist third-party solutions for each OS, so you'll have to practice some Google Fu to find the best one until an official solution comes along.