I have both iStrelok and Strelok Pro on my iphone 3GS. I also have Ballistic (powered by JBM software). This same software is available on Android platforms as well.
For a new shooter, 100% iStrelok IMO (Strelok+ on Android). What I like about this program is there seems to be a good balance between precision and ease-of-use. You can build up your rifle/scope/cartridge options and easily switch between them. It also has real-time hold calculations for pretty much every BDC reticle on the market. This is also good for a new long-range shooter, since you are most likely to have a BDC reticle of some kind. I have used the program to get a solution for a few rifles out to 855 yards, and results varied from first round hits on a 12"x12" to being out by 1MOA.
I need to mention that on that occasion, environmental data was entered in a hurry, and the rifle that was out by 1 MOA had no chronied velocity at that time.
iStrelok has some slightly advanced features: trajectory validation, zero weather, temperature stability, turret click calibration. It does not have Coriolis, spin drift, or G7. For those features you need StrelokPro.
I have to warn a new shooter off of StrelokPro however, at this time you cannot enter an altitude & baro pressure. You can only input station pressure, like what you would get out of a decent Kestrel unit. Sadly, it does not have density altitude as an option either.
Igor is steadily updating this software, so improvements will likely keep coming.
One last feature that I really like is the ability to upload/download your rifle/scope/cartridge info to a Dropbox account. Set up your stuff, upload it and keep it up to date whenever you make a significant change. When you move to a new device, you just download it and you have 0 set-up time on the new device.
Shooter eh? Bryan Litz eh? This canuck has to go buy another app I guess. I just like trying them all. I'll update when I get a chance to compare it to Strelok unless someone beats me to it.
