You'll need to get much more specific.

WHO is the audience?

WHY would they want these "gadgets"?

What problems are you solving, for what audience, that they will pay you to fix?

Do you know what size problem warrants your involvement?

Honestly, your question is so vague right now it can't clearly be answered. Niche it down. You're matching up a buyer with a seller. Who are these people?

It sounds like you'd like to be in a position to help startups grow, and know strategies for that.

The answer is that it depends on what you'll be doing and the nature of the startup you're helping. There are a number of generic tactics you can use, however it mostly depends on the nature of the startup you'll be helping.

Not all of startups might want to grow internationally. For those that do, they might not have a hard time growing outside of their country, it depends if their offer can be monetized outside their regions and traditional markets.

Give us an example of a startup, and while you're at it, here are some quick generic strategies: http://blog.import.io/post/10-minute-growth-hacks-that-will-jumpstart-your-marketing-strategy

hello, I'm a growth hack marketer and MBA growth and sales coach.

I'm not sure what your intent it, but I would assume that you are considering in doing this yourself. If that's the case then being a growth hacker would already know the answer. find the applicable interested parties, the websites where they congregate, venues, find out their interests, then find a single focus of need across these startups and promote your services to the world around them- hack your way in front of them. Use this a test to prove your GH abilities.