Thanks guys. I have toured before. I've also backpacked over 4000 miles. I do intend to look up route and take screen shots and keep the phone in airplane mode while riding so I'll be using the online copy only and not reliant on data. Nonetheless there still is the issue of days of riding through areas like North Dakota that will have no service whatsoever. Perhaps maps might serve me better in these areas. The issue of overheating that I'm referring to has nothing to do with overuse of phone and all to do with heat generated from the sun. Try putting your phone on a picnic table on a 90 degree sunny day where the sun is shining on it. Within 30 minutes the phone will overheat. This may be an argument for the handlebar bag instead. (Prior tours I've used maps.) And maybe you are correct that I am overestimating the necessity of needing my phone as a directional aide. Thanks.