You could use one of those chargers that plug into the cigarette lighter and have a USB connection on them. They convert 12Vdc to 5Vdc. Heaps on Ebay for under $2 delivered. They would use much less power than the inverter which converts 12Vdc up to 240Vac and then down to 5Vdc. Just put "car charger for ipad" into Ebay and you'll find big mobs. Good Luck.
I have a 12v TV, 12v supply for my laptop, and 12v chargers for my cameras and phone, minimising my need for an inverter. When not on a powered site I take advantage of the sunshine and do my device charging when the main battery is on charge from the solar. The cameras and phone can also be charged in the car while driving along, likewise your Ipad if you have a 12v charger
I also got 12v chargers for my phone, iPad and laptop. I didn't know you could do this for the digital cameras, so thanks for the heads up. Our caravan has 12v car chargers set up inside and outside the van, for this purpose.
I have a double USB outlet that plugs into the cig lighter and charge both the statphone and IPad from the single point About $9.00 from JayCar cheaper on ebay if you can wait a few days
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Pets are welcome but children must be leashed at all times
Do you have a Solar panel on your camper ? for most things we use 12 volt from the battery ( TV _ Lights_hard drive ) we try to charge the gadgets all at once ( what never works out btw ) got an 4 way powerboard connected to the inverter (150 watt) where everything is plugged in we do that all from a 100 amp battery and 80 watt solar panel so far we are lucky and never run out
