MyFlightBook captures its data directly. You open a new log entry, press on the Engine Start field to populate it with the current date/time, and from there it tracks your flight (both in the log entry by making note of airports you visited and landings, but also recording GPS info -- which you can look at later on the website by clicking on the paperclip icon to see your ground track, altitude etc.; or in the app by pressing on the map icon in General Flight Information for each entry). After each flight, when you stop the engine press the Engine Stop field to place the date/time in there, and enter the Ending Hobbs time if you want (Starting Hobbs is already populated from the last flight's Ending Hobbs when you open a new log entry).
But if you're looking to load data from past flights -- someone else will have to pitch in with that info.