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I've done developing my app in C#. I need some info of how I can implement 'trial' functionality for my app (I want to let the user use the app for 30 day for example)
I've done developing my app in C#. I need some info of how I can implement 'trial' functionality for my app (I want to let the user use the app for 30 day for example)
A specific commercial solution I've used is from Aladdin. They offer a USB dongle or a "software dongle" that allows you to pick and choose what features are enabled/disabled. The USB dongles even come with a battery-operated clock sealed in them so that gaming the system clock doesn't get around your protection.
Some people may say that any system like this can be broken. This is true. However, I've found Aladdin tools can be used to make cracking very difficult. Pair that with improving your protection on subsequent releases and what you get is a product that takes a lot of time and effort (cost) to break.
There's a related discussion on this SO question: Software evaluation licensing.
You can also check LicenseSpot which gives you the ability to control the license via the online license manager with activation, revoking and trial extensions.