Please make the calculator as self-running app on Chromebook, just like Scratchpad or Google Talk. This would it make much easier to use it while Multitasking with Google Docs. Keep up the good work!
Thank you for the idea. Have you tried Calc extension for this case https://chrome.google.com/webstore/detail/aehdbdldgkmjaalcdojemaeemhionghd ? It may work for you for now