RealPlan considers winds when it solves for your route. Running it at different times (and thus with different wind conditions) will yield different results.
If you have multiple devices, one option is to run RP on the fastest device and let it do the work, then use iFly's flight plan sync features to share the resulting plan with your slower device(s).
If all devices you want to share between are currently on the same wifi network, then you can share directly between devices via Flight Plan > More Options > Share with local devices > Share Plan. (Do that on the device you used to get the RP solution, and then look for the subsequent popup on your other device(s) on the network to "Accept shared flight plan".)
Alternately, you can upload the flight plan to the iFly cloud and then download it later on other devices. On the device used to solve RP, go to Menu > Setup > Sync devices... > Upload files to server..., then make sure Flight Plans are selected, and click Upload. Then, on the device you want the flight plan copied to, go to Menu > Setup > Sync devices..., then click on the device you just uploaded the RP flight plan from, make sure Flight Plans are selected, and click Download. (Each device will need to have an internet connection when you do this, but since the data is stored indefinitely on the iFly cloud server, they don't both have to be online at the same time.)