A while back I posted about how to install apps from outside the marketplace onto your Windows Phone 7 or 8 device, in case you missed it check out the posts down below (plus videos!)
Step by Step Instructions can be found HERE
I constantly got some questions regarding how this would affect users devices in terms of support, updates and others; so here;s a quick run down.
To make things clear enabling a developer unlocked account on a Windows Phone is completely legal, and allowed; it doesn't "hack" your phone in any way, it simply allows your Live ID to install unauthorized apps through your PC rather than only allowing marketplace apps.
Will this affect future updates on my Windows Phone Device?
No, your WP device will continue to receive software and application updates as before (however side-loaded apps CANNOT be updated though the marketplace).
-Will this in any way "brick" my WP device?
Absolutely not, as mentioned this is a completely legal and safe process, so don't worry.
-Will this work on my XXX Windows Phone?
YES! This process works on ALL Windows Phone devices, regardless of the OS (7.0/7.5/7.8/8 etc.) or manufacturer (Nokia/HTC/Samsung/ZTE etc)
-Is this process reversible?
Although there is no need to "reverse" the process since nothing is changed it is indeed reversible.
-Will this void my Warranty?
No, technically your hardware warranty should still be active, since you're not modifying the software in any way; however some beta apps may lead to bugginess on your WP device, so install your apps carefully.
-My device says I've reached the app limit, what now?
The free .edu developers account has a maximum limit of installing 10 side-loaded apps at once, there is no way around this; the only solution is to delete an app and replace it with another.
-Is this a permanent solution?
Sort of, your Live ID needs to verify the .edu account it's linked to every year; meaning as long as you have a working .edu email address you won't have any trouble, you may be prompted once a year to re-verrify your .edu email.
-Will this affect my battery life, phone performance, speed etc. ?
Absolutely not, as mentioned before; some beta software however may increase battery drainage.
-What if I purchased a new Windows Phone device?
As mentioned the only thing modified in this process is the Live ID; meaning that once you sign into your new WP device with the same Live ID you can instantly side-load apps, without having to repeat any of the steps.
-What type of PC/Operating System do I need?
For Windows Phone 7 Devices any OS is fine, for WP8 devices you MUST have a Windows 8 PC capable of running the Windows Phone 8 SDK
-What if I have a Mac?
Tough luck, the process requires a functioning Windows device (see previous questions).
-I don't have a .Edu email address, what can I do?
Unfortunately not much; there is no other option, short of asking a friend to use his/her .Edu email. Sorry.
-What sort of App files can my WP side-load?
the WP app format is .XAP (pronounced Zap)
-Where can I download pirated games?!
Don't, support app developers. Download Beta software and tweaks from the XDA developers blog