We are trying to decide between a presales strategy and free/freemium app store launch for our mhealth self management app. Which should we pursue?

It really depends on whether this is ultimately a top-down or bottom-up approach and to what extent the end-user experience is compelling enough to act as a forcing function to enterprise adoption.

A bottom-up distributed mobile app must be both viral and incredible engaging. Without proof that you have that (or absent proof, strong conviction) most are better off attempting to sell top-down.

Happy to talk this through in a call

You need to ask yourself what your greatest risks are for your business. Especially since you're self-funded and bootstrapped, I would not wait to validate whether people will pay for your product.

The beauty of someone paying is that not only does it validate interest, but they are then *invested* in your solution. They now have expectations for what you are going to deliver to them.

On the other hand, think about all the free stuff you pick up at conferences, trade shows and walking down the street. How much of it was there ever a chance you'd pay for it? Much of it is unlikely you would. That means you run the risk of having people kick the tires on your product and never be really interested in what you're doing or paying anything.

Happy to talk further and help you better approach your customer discovery as I've been doing custdev interviews for 4+ years.

Freemium all the way... but with a twist. First and foremost develop the product to the point where your workflow works and doesn't break in the middle. Then open the platform out to the public for a dollar, of course with the exception to try it out for 14days. When they sign up you are able to build an email list and if done right that's enough marketing. Make sure you optimize your product for the most useful keywords and request to contribute a guest blog or guest blogs in popular blogs or buy ad space on buysellads.com, create an animated ad and let that run.
Do the usual as well, create a twitter and facebook app. Release a Short ebook on your website on some important problem that your platform fixes, write a press release and reach out to your friends to share and re-share one of your blog posts on social media.
And by then you'll be quite famous and if your product is very useful you'll also be cashflow positive, resisting the temptation to say, "rich". Then you can do a update coupled with an email blast and you then release your finished version as an update, and monitor and learn from your users via intercom.io.
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