Went through a lot of them.
For freelancer it is most convenient www.tahometer.com
- ON saves the screenshots, gives statistics on clicks etc. is Stored in the cloud. Very comfortable and gives a fair accounting. There is a free tariff. Of the minuses - very clumsy navigation.
There are still bitrix24 crm system, but there is a time tracking clumsy. It is, but do not give the client assurance that he is real. If just for show - suitable.
PhpStorm has a built-in time tracker that integrates with their service. Have not tried, because of the high cost and very abstract description. Can be convenient. If anyone tried it - drop me a line.
There are a lot of services. but they are more aimed at companies and not interesting to the freelancer. Or take into account just work in one way or another program that does not allow pictures.