$ sudo apt-get remove gif2apng 

Uninstall gif2apng including dependent package

If you would like to remove gif2apng and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove gif2apng 

Use Purging gif2apng

If you use with purge options to gif2apng package all the configuration and dependent packages will be removed.

$ sudo apt-get purge gif2apng 

If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.

$ sudo apt-get purge --auto-remove gif2apng 

See Also,