You might consider one of the many spreadsheet apps available. Set up columns for whatever you'd like to record - things including date, tasks worked, hours spent, etc. Spreadsheets are nice because they can be setup to automatically total your time spent on the project as well as specific sub-assemblies (emp, wings, fuse, etc.) Make it as simple or as feature-rich as you desire. You can even link photos taken with your mobile to specific entries if you choose.
Eric
, and second, I was asking about an Android based Pilot flight time log app. I'd like to be able to log each flight into my smartphone at the end of the flight.