hi marco,
APRS2SOTA has become my first choice for selfspotting! i love the idea of not having to use the mobile phone and totally rely on my ham radio equipment. but you should keep in mind that an i-gate needs to be in reach to relay your message to the internet. for my hikes with poor aprs coverage i built myself a portable i-gate … see more info here:
i use a kenwood th-d72 for aprs. i have two previous sent messages stored (one for hf, one for vhf) as some kind of a template and edit it. if you have a tx i-gate in reach you instantly get a confirmation message that you have been spotted.
73 martin, oe5reo