Is there a way to make people "subscribe" to your program?

I make a simple program. The program is simple. Basically add friends and confirm friends. Allow people to quickly increase their friend to 5k.

Then I will make another simple program. Basically spam your friends with texts.

I can set this up as service. Or I can just let users run it by themselves.

NOTE: I am NOT selling the program yet.

How much do you think I should charge for this?

If it's a service? How much?

If it's a program, how much should I charge per month? Should I charge per account? 5k friends, .5 cents each means $25 to make your facebook account full of friend? Is that a reasonable fee?

Basically I would need a server that track down people's credit. Every time an act is done, I would deduct money from their balance. Would that be a good idea?

I am thinking of selling stuffs in apple playstore too.

How do people make money here?

Spamming only hurts a business, and very often only works for a limited time before it is crippled. Focus your attention on something that's legit.

Is that an online tool or does it need to be downloaded?

The friends adding feature is great, however be cautious when mass texting, if accounts are getting banned after using your tool, people will stay away from you.

How about letting your users purchase coins and charge 1 coin per action (successfull added friend)
If your tool is able to add active users from a specific niche (for example adds fans of a specific page) and gets quality leads this way, you may charge far more than 25$ for 5,000 friends, but make sure to start with low prices so people start using your service.

Also think about implenting a service like paymentwall, so people can use your service "for free" by completing offers like watching videos / answering surveys.

I wonder if there is such service already