Treejack is another great UX tool from Optimal Workshop. Treejack allows you to test an information architecture (IA) by carrying out ‘reverse card sorting’. You upload your IA, which might be the site structure or a taxonomy used then ask users where they would go to find something within a clickable navigation tree of your IA (see screenshot). The free version of Treejack allows you to test up to 3 tasks with up to 10 participants.