You can install our site as a web app on your iOS device by utilizing the Add to Home Screen feature in Safari. Please see this thread for more details on this.
Note: This feature may not be available in some browsers.
(moderator note: OP says "model s on order", so moving to the model S subforum for specific advice for model S vehicles. Model 3s and Ss charge at different rates so this advice might be slightly different for S than 3 (or not).