The 2.0 revision of X-Ray Timer has been approved by Apple and is in the App Store.
This revision added Se-75 as an Isotope selection. I used the values by the manufacturer for the radiation output and the published values for the shielding value of the steel. I don’t actually own any Selenium sources myself, but several people requested this feature.
I decided to go ahead and make this app free for the community. Sales dropped off enough to the point I wouldn’t really get paid anymore so I decided to make it free for everyone. Hopefully now it will be the new standard way work is done. Spread the work around.
I’m working on a Web App version for computer browsers and other smart phones.