Study Bible Apps?

I'm inviting folks to share their favoured Bible apps for their tablets, etc.

Sure, one can read the feedback reviews that are attached to the myriad spread of offerings out there via Play Store, but I'm also interested in the perspective of folks at this site, if this is pertinent for you.

I currently use the free version of the NIV on my tablet. A hardcopy Bible isn't always handy on the church pew, but beyond that incentive, I'm looking to purchase a study version that also would supply historically accurate maps as well as the usual cross-reference information.

So if you have pursued this type of product with any degree of success, do feel welcome to share, here. I, for one, would appreciate your input.

Thank you!