Gett Taxi is not like Uber. It's an app that dispatches and pays a registered taxi. You can use it to call a taxi to your location. It worked pretty well for me, but it failed on the edge of the old city of Jerusalem when it couldn't locate my position adequately.

Israelis will warn you to make sure your cabby "turns the meter" without telling you what that means. Israeli taxi meters are mounted on pivots. The driver has to physically turn the meter to switch from the available to the engaged position. If he drives away without doing this, he's robbing you. I wish I'd had the presence of mind to call the police when this happened to me. I rather doubt they'd have done anything, but it would have gotten the cabby's attention. I can only plead jet lag.