My absolute first advice would be not to launch the app at a low price then raise it up later on. That's an absolute No No.

There is no real rule to price your app. My suggestion would be to look around the app store of similar apps to get an idea of what they are priced at.

Once you launched the app at a certain price you can always have limited time deals. Keep an eye on the downloads and price. By doing this you may be able to find the perfect price that gives you the most sales and can change the price accordingly to that.

Pricing does depend on the app itself. In general, since a lot of people are interested in mhealth, I would encourage you to think of a freemium option that would work well.

For pricing our apps, freemium has always been more lucrative than a paid app. I have a theory that most people want to try software before paying for it.

For blogs, I would encourage you to embargo publishing information till you are live in the app store (bug free). Keep in mind, that there may be delays in testing and app store review.

Happy to talk more if you need specific advice.

Cheers,
Aditya

If you honestly feel the tool is addictive go low with it at a beta release level. Depending on the retention of the tool scale accordingly on the final product or consider offering a 2 price point system allowing for a basic level that would be beta and a premium providing full value of the tool.