Sheenagh and I are currently travelling through Europe for six weeks and I thought I'd share how we're managing our photos so they are backed up.
Sheenagh has an Olympus E-M10 camera which takes a standard SD memory card. She also has an iPhone 6. I have an iPhone 6 plus (which, by the way, I think is too big) and an iPad 3 (120 GB).
While travelling I bought a data pack from my telecommunication company (Testra) that enables me to use all the connectivity functionality of my iPhone across the countries we visited. It cost a couple of hundred dollars for a month. Sheenagh turns off her Mobile Data and Data Roaming and just uses wireless wherever it's available.
Our approach relies on having fairly good wifi connectivity for overnight uploads to the cloud on a regular basis. We didn't get this every night but every few nights worked fine over the six weeks we were away.
Backing up our photos
At the end of each day we'd take out Sheenagh's SD card from her Olympus and use an Apple Lightning to SD card reader for the iPad and import all her photos to the Photos app on the iPad. When you insert the SD card into the reader a new icon appears in the Photos app on the iPad called Import. Select all the photos and hit Import then delete them off your SD card.
We'd then Airdrop any photos she took on her iPhone 6 to the iPad.
Since I'm using iCloud Photo Library all the photos automatically sync to the cloud and then are shared with my iPhone Plus.
Experience has taught me to never trust a single backup source so I've also enabled Dropbox on my iPad to automatically upload new photos whenever they appear. The upload can take some time so this is where you need a good wifi connection that you can upload overnight. Each morning we now have two backups as well as all the photos on the iPad.
So now you're set. This regular routine ensures your precious photos taken on the road are kept safe.