After a purchase, you typically get a paper bill/warranty receipt and there's a high chance that this slip of paper will get misplaced or damaged. With a free app called Warrantify (available for Android and iOS), this problem is taken care of. First, you scan the paper receipt (i.e., take a photograph using your phone's camera). Then, you need to enter the relevant details (product name, model, warranty validity in months, price in USD/INR) and then save the details. The receipts are also uploaded to warrantify's central server so that they can be accessed online from the warrantify website.
Click here to download.
Click here to download.