- A PC or Mac ($300 Vs. $700)
- Internet access (???)
- A developer account ($35 one off, or $99/year)
- A business address (PO Box for one year, approx $62/year)
- Electricity
- Minimum wage at whatever number of hours your app takes to make
- Business licence (if required? see local laws)
- Cost of an accountant (if required?)
- Marketing/SEO costs
- Hosting, domain renew, SSL certificate renew, email, et al.
- Other external resources (e.g. graphics, sounds, et al).
I'd say if you had nothing but a roof over your head and food in your belly you could do it for $600-1K a year including getting a new low end developer machine annual (or other equipment, like second monitors in subsequent years).
$600-1K might sound like a lot, but all the little things add up quickly. This also only covers the cost for a VERY simple basic app. For "AAA" style apps we're talking millions or more.
If you have to ask how much without a laundry list to go from, chances are you can use Cordova to get your app going. In Houston, basic apps using it can go from $1K - $5K.
https://raddevelopment.io/blog/want-to-ask-a-developer-how-m...
I am a hobby iOS developer, and it is the appearance that suffers the most on my low-end products. If you can do your own artwork then you can get by for about $0+your time.