But as the world was glued to the unprecedented meeting, we also learned that Kim likes a selfie and that Trump is really, really proud of "The Beast", his armoured car.

- Bring the boys home -

In a jawdropping post-summit press conference lasting more than an hour, Trump said he wanted to bring home the 30,0000 or so US troops currently stationed in South Korea.

Picking up a theme he had hammered on the presidential campaign trail, but which worries allies in Seoul and Tokyo who rely on US defence, he said: "I want to get our soldiers out. I want to bring our soldiers back home."

He also called a unilateral halt to "very provocative" US military exercises with South Korea, claiming they were "very expensive" and the US pays for "a big majority of them".

- Sleepless in Singapore -

Summitry is hard work and Trump claimed he "had not slept for 25 hours" during his time in Singapore, which lasted just under 48.

The US president had an unusually light public schedule the day before the summit and holed up in his hotel the whole afternoon and evening -- although he was tweeting very early on D-day and again on his way to the meeting.

Kim also proved to be a secret night owl, stunning onlookers in Singapore by going on an unannounced night-time prowl of the city sights, accompanied by a horde of aides and security officers.

- Air Force Un -

Before the summit, several commentators wondered how the travel-shy Kim was going to get to Singapore, having not flown such a distance since coming to power in December 2011.

In the end, he simply hitched a ride from his pal President Xi Jinping on an Air China Boeing 747 -- a surprising move given North Korea's insistence on "juche" or self-reliance.

The crew had social media users and planespotters scratching their heads with some aerial subterfuge, changing call-sign midair over China.

It may have been a safer move than taking his usual aircraft, a Soviet-made Ilyushin-62 dubbed Air Force Un -- although his sister and close aide Kim Yo Jong reportedly used it to reach the city-state.

- Location, location, location -

According to former hotel developer Donald Trump, the beaches of North Korea offer ripe opportunities -- although he gave a slightly sinister reason for knowing that.

"They have great beaches," he said. "You see that whenever they are exploding the cannons into the ocean.

"I said, 'Boy look at that view.' Wouldn't that would make a great condo? I said, 'Instead of doing that, you could have the best hotels in the world.'

"Think of it from the real estate prospective. South Korea and China, and they own the land in the middle."

- Selfie star -

Kim capped months of a diplomatic charm offensive by posing for a public selfie for the first time -- a far cry from his usually carefully controlled image.

The photo of a grinning North Korean leader, taken and posted online by Singapore's foreign minister Vivian Balakrishnan, astonished social media users.

Not everyone was impressed, though.

"Is it worth taking a picture with a tyrant? It's your shame," said one user @huangyonghua.

- 1 in 10,000 -

Gone were the days of "little rocket man" and "sick puppy" -- names Trump had previously used for his summit buddy.

Now Kim was praised as "talented", "very smart", a "good negotiator" who "loves his country very much", according to the US President, who even showed off his armoured limousine to the North's leader.

Few people could take over North Korea at the age of 26 and "run it tough", Trump mused. "1 in 10,000 couldn't do it," he added, with the caveat: "I didn't say he was nice about it."

Pressed on the fate of Otto Warmbier, the US student who died after being held in North Korea, Trump said relations started to change with Pyongyang at around the time of Warmbier's death.

"Otto did not die in vain," he said.