I just want to thank all you folks who helped me out on this. You explained what I needed to know quite well. lI decided to get the iPad mini with Retina display 64gb with wifi and 4g LTE. I talked with a Verizon rep and the best deal while remaining on the 200 65 plus plan (no longer offered-I don't talk much on phone and do not text) is to keep iPhone5 on 2gb data plan and add iPad mini at 2gb, 3gb, etc. I can use iPhone for emails and maybe streaming music. The iPad mini will be used for GPS, videos (limited) and research while we travel.
The rep also said that we could suspend the plan up to 90 days twice a year but that for each 30 day period suspended we would add on to contract. Purchasing the iPad mini using the 2 year contract with Verizon would cost around $685 including WA state sales tax. Buying the unit from my trusted out of state retailer w/o sales tax and free shipping is $729. So the 2 year contract makes a bit more sense financially. Just my right brain analysis.
I also found SD card reader for around $30. I like the idea of the wireless hard drive (thanks Fizz) and may possibly get one in the future. But, I think 64 gb will do for now with the mini. The one suggested was rated the highest so it is in my wishlist at B&H.
I also like that the apps I have for iPhone5, unless specifically for iPad mini, can be used on the mini, also. I am on iCloud so I think I should be able to figure out how to use it. The local Verizon store said they could help me transfer files on Mac to iPad mini and get me started.
It's a lot of money but the advantages are worth it:
We will both be better able to see the screen for GPS while we are traveling
I can download eBooks and maps to eliminate some of what we pack (important in a pop up TC)
The travel info stored on my Mac can be accessed on the mini for more info while on the road: pdf brochures; info saved as pdfs on photography and rockhounding locations, etc.; photos of where we want to go so DH can see why I want to go there
Internet access to research an area while we are there and if we see a sign to somewhere intriguing, we can check it out (if we have a signal).
Transfer jpgs to show others what I shot and also to critique my composition on the spot (if light isn't fading fast). Also, to show bands I shoot so they may want to buy my photos.
Goldilocks value: not as small as iPhone but smaller and less cumbersome than 4 year old macBook Pro 13".
I can also use the USB charger that plugs into the 12 volt receptacles in both camper and truck eliminating yards of cords and an inverter. It has USB outlets for iPhone and tablet
Convenience of not trying to find wifi hotspot (we travel to remote areas and boondocking doesn't include wifi.)
And, more I can't think of now.
Apple all the way: macBook Pro, iPhone, iPod classic, iPad mini. Proprietary and expensive, yes. Ease of use, synching, quality, design (right brain thing again) worth it.
Thanks again.