This lesson is free for the first 7 days. To access this lesson after that and to all the other lessons, it costs $4.99 per month. Here’s an excerpt form this lesson – A good place to start your search is a site called AlternativeTo. By typing the name of the patent application in the search box, AlternativeTo will show you any alternative applications available. People can Like an app to let you know how well the app replaces the commercially popular application. For example when searching for Photoshop, the free app GIMP is the most popular on the list. You can also sort by license. This means you can filter the results so only the free and open source programs are shown. If you are looking for an online version of an app, you can sort by platform too. Mac, Linux, Windows, Online and lots of other choices are available.