Amazon Kindle fire slowed down abruptly

My kindle is slowing down and it is becoming very annoying to restart the kindle every time it hangs. I had bought this 2 years back and was fully functional and the performance, clarity of the picture and the quality of sound was top notch. Now, from the recent past I observed that it hangs even if I just browse, doesn’t support third party apps well. I removed all the apps retaining only Skype. Still the problem persists and I cannot use Skype too. It has made the kindle useless to me and has to sort out this at the earliest. What could be the issue?
