When comparing Synapse vs Ulauncher, the Slant community recommends Ulauncher for most people. In the question“What are the best Linux app launchers?” Ulauncher is ranked 5th while Synapse is ranked 6th.
Ranked in these QuestionsQuestion Ranking
Pro Rock solid
Synapse is pretty rock solid. Works as expected and launches applications fast.
Pro Includes a Zeal plugin
Includes a Zeal plugin to make searching faster.
Pro Can run commands just as a terminal would
Users can run commands such as
sudo apt-get update from within Synapse, making for a convenient way to open or run items/commands.
Pro Zeitgeist powered
Synapse searches the Zeitgeist log, which tends to be a pretty quick way to do searches over other app launchers.
Pro Supports extensions in Python
Pro Able to launch Kdialog, Zenity and Bash scripts
Extensions are easily created. Python script is all open to see. Not compiled like some.
Pro Supports fuzzy search
You can enter app name with a typo and Ulauncher will still be able to find it.
ULauncher supports themes and comes with a good supply on install but more can also be made.
Pro Allows custom shortcuts
Con Unable to search whole system
Due to Zeitgeist being used the search is not as robust as if it were using Tracker. Of course using Tracker has its own downside like battery drain, so currently there is no "best" solution.
Con Bound to control+space
Due to this it interferes with common IDE layouts for recommendations. Modifying hotkeys file doesn't adjust this.