If you're looking for a time tracking system that can be used from multiple device types then take a look at Time Lucidity from Gill & Piette.

We'll work with you to closely integrate with your existing systems to create an easier way for your employees to track their time for billing and any other purpose.  We can take data from your existing systems so all important fields are validated at time of entry.  Built-in features like date-pickers and spell-checking help assure clean data that will import smoothly into your existing system.  Time Lucidity will run on any internet connected device with all modern browsers.  This includes tablets and even smartphones.

Click the stopwatch  and use these credentials to try it:  Username - demo, Password - c4Myself