Now that we have a bit more information, I say, get two iPad 3G units for the trip. Establish your iCloud account about two months before you leave and practice your upload procedures.
There are other tablets on the market, I have used Apple products for twenty-five years, I don't know or care about anything else.
You will want these items in your financial and mass budgetrs: Protective, possibly armored and waterproof, cases for two units; auxiliary charging systems, possibly solar, but likely simply an extra set of li-on booster batteries; camera connectors and cable kits; and maybe an entertaining iPad user book.
Any digital system is subject to loss, theft, damage or destruction. You risk losing your entire trip's archives if you do not have any kind of back up process. You will want to know you can move your data off your iPad and up to the cloud at reasonable intervals or you will want to protect your data in some other way.
Plan carefully, rehearse and practice your data protection, enjoy your trip. Do good things and meet interesting people.