These days, people are starting to take full advantage of their cell phones and I am no exception. If you haven't already started viewing your phone as a virtual Swiss Army Knife ...then maybe you should because you're missing out big time. I believe it is absolutely essential to have a Unit Converter app on your phone, and the best one that I have found is, believe it or not, called "Unit Converter" by Wopnersoft (ANDROID). I use this app all the time and have found it to not just have more options than other converters but a simpler layout as well. Radiation units in absorbed dose, dose equivalent, and activity are all there for your disposal.
The best CALCULATOR app for android that I have found is called the "RealCalc Scientific Calculator) by Quartic Software. Here are the rest of the Rad Pro related android apps that I recommend you take a look at :
1) "Half-Life Calculator" (solves for everything)
2) "Periodic Table" by JQ Soft
3) "Radiation Calculator" by Tobias Magnander
4) "Nuclear Wallet Cards" by Brookhaven National Lab OR "Isotope Browser" by IAEA Nuclear Data Section
5) "Nuclear Data Search" by Tobias Magnander
6) "Mobile Remm" by National Library of Medicine at NIH
If you have any other useful suggestions for android or apple Apps that have helped you out in the field please don't hesitate to list them. (P.S. I know there are some HAZMAT related apps out there too but I can't remember them)