XLSForm Online v2.x
Convert an XLSForm into a form that you can upload to ODK Aggregate or temporarily preview in a browser.
ODK Aggregate is no longer being updated. ODK Central, its replacement, has built-in XLSForm preview, lets you group forms into projects, and has no limits on form updates. Get started on ODK Cloud
or read the docs
XLSForm Online has had major improvements. If you have problems updating an existing form in Aggregate, try XLSForm Online v1.x.