The posters who mention apps for charging do have a good point. Can EA, Tesla, and other charging apps run on the older phone? They can be awfully important when Plug&&Charge doesn't work. How about PlugShare, ABRP, Google Maps, and other planning apps? If those work, FP is less critical; if not, the purchase of a newer phone may be justified for several reasons rather than one.
EA, Tesla, PlugShare, ABRP, Google, FP, and the C logical and are trademarks owned by their respective owners and are used in this post only to identify services. No endorsement or indictment of any particular service is expressed or implied by their use. The author of this post does not assume any responsibility for any failure to charge in a timely fashion due to malfunctioning chargers, power outages, overheating adapters, Juiceboxes(tm) in general, too much time and not enough useful things to do this evening, nor the presence of Bolts at a fast charging station. Do not taunt Happy Fun Ball(tm).