The Userback API utilizes Filtering and Sorting based on Microsoft API guidelines syntax, excluding the use of $.
Filtering
In order to filter records you can perform an equality check like so:
https://api.userback.io/rest/1.0/feedback?filter=name eq 'Joe'
Or utilizing gt to find all feedback with more than 5 votes:
https://api.userback.io/rest/1.0/feedback?filter=voteCount gt 5
Filters can also be combined using the and/or operators:
//api.userback.io/rest/1.0/feedback?filter=voteCount gt 5 and type eq "BUG"
Sorting
https://api.userback.io/rest/1.0/feedback?orderBy=modified desc