David Mayman, a former commercial pilot, flew at a height of 30m for four minutes wearing a turbine jet engine-powered JB-10 jetpack.
He hopes to make an electric version of the jetpack to be available in 2019 - at a price of nearly Â£200,000.
Mr Mayman said: "It feels absolutely amazing, awesome - it's freedom."
The project to develop a commercially viable electric jetpack is seeking to raise Â£300,000 through crowdfunding, with work on the project planned to start in April 2017.
The Australian former pilot took off in the jetpack from the Royal Victoria terminal of the Emirates Air Line cable car by the River Thames and made two short trips towards the ExCel centre.
"This is for the City boys who grew up in the 70s and 80s and dreamt of being a real-life Iron Man," said Lucy Sharp from Seedrs Investment, the company behind the fundraising for the electric jetpack.
"He's in talks with the US navy to give it a use beyond commercial flights.
"He's done over 400 test flights and they've all gone smoothly but it is jet fuel on his back so it can be dangerous."
The former pilot, who has worked on the project for more than a decade, has previously flown close to the Statue of Liberty in New York City and in Monaco.
Engineer Bennie Van De Goor said Mr Mayman's "passion for a long time has been to develop a small man-carrying vehicle that he can put in his car, take out and fly".
A pilot wearing a jetpack has taken to the skies above the River Thames in east London like "a real-life Iron Man".