1. Ape Escape was the first and only PlayStation one game to be developed
solely by Sony Computer Entertainment Inc. and not by a Sony development studio. It was developed after SCEI were unhappy about developers first and third party not taking full advantage of the DualShock controller. Ape Escape uses every single button on the DualShock and was the first game that required the analogue sticks.
2. Crash Bandicoot was used as the PlayStation mascot up until 1999 when Sony pushed the Pipo monkeys from Ape Escape due to Naughty Dog giving the franchise up.
3. Naughty Dog sold the Crash Bandicoot franchise to focus on another franchise to replace it (Jak and Daxter) as Crash's sales had died down since it's launch.
4. Crash Bandicoot was picked up and made multi-platform and saw huge success before poor sales soon returned to the franchise with it being shelved. It's still considered Sony's most recognizable mascot.
5. Spyro suffered the same fete as Crash Bandicoot, with Insomniac games giving up the franchise as the PlayStation 2 was approaching, as Insomniac wanted to work on a different game for the PS2 era. Luckily, Spyro was also made third party to huge success and has had 3 different series since Insomniac gave the game up.
6. Due to the unexpected success of Ape Escape, the game was re-released in 2005 for the PlayStation one, a year before the PlayStation 3 was expected. It was also the first game to receive a port to the PSP (and was the first port Sony had made) in 2004.
7. Sony sold half the rights of Ape Escape to it's Japan Studio, but kept half as they had more idea's themselves for the franchise.
8. Sony were disappointed with Jak and Daxter originally as they didn't think it was as good as Crash Bandicoot. They also felt the same for Ratchet & Clank before it's release, especially when Ratchet was supposed to be a lizard type alien. Sony requested Insomniac find a better protagonist. Ironically, both Jak & Daxter and Ratchet & Clank proved to be bigger than the franchises they were replacing.
9. Naughty Dog assisted with parts of the development of Ratchet & Clank, after Insomniac requested help and advice. Naughty Dog and Insomniac continued to help and work with each other on each of their games and both developers were inspired by each other to work on more adult games such as Uncharted & Resistance.
10. Sony Computer Entertainment Inc. also worked on two more games for the PS2, and another for the PSP. All three of them were based on the Ape Escape series. This attempted to bring a much darker side to the series, which was the opposite of what Japan Studio aimed to achieve.
11. In order to make Ratchet & Clank more popular in Japan, Insomniac made a deal with Sony to allow the Ape Escape monkeys to appear in the third Ratchet & Clank installment in Asian copies. They also asked if Sony could feature Ratchet & Clank in an Ape Escape game.
Although Sony agreed, they only included a monkey dressed up as Ratchet and Clank rather than Ratchet actually appearing in the game. Ratchet monkey appeared in Ape Escape 3.
12. A monkey bonus round was featured in Metal Gear Solid 3. Japan Studio returned the favor, including a Metal Gear Solid mini-game in Ape Escape 3.
13. Jak & Daxter have not had a full game on the PlayStation 3. Naughty Dog have pushed the franchise aside, however the franchise was featured in PlayStation Move heroes and PlayStation All Stars: Battle Royale.
14. Ape Escape received an Anime based on the show that is currently awaiting a third season. They also received a US TV show which was recently made available on DVD in the US & UK.
15. Ratchet & Clank has had the most amount of games released WW. It was also the first game to have a mobile game in 2005 and to also have a full iOS and Android mini-game to promote Into The Nexus.
16. Ratchet & Clank are receiving their own movie with games expected to be based on it.
17. Despite Naughty Dog and Insomniac often sharing idea's for each others games, Naughty Dog has had no urge to reboot Jak and Daxter as of yet.
18. The first Ape Escape and Jack and Daxter both received a 90 on MetaCritic.
19. Ratchet & Clank is Sony's most popular plat former franchise.
20. Knack was expected to have the same impact as Ape Escape, Jak & Daxter etc. but so far hasn't caught on.
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Add any interesting facts about Sony's first party games!!!
Doesn't have to be platformer's
I only know the info behind Crash, Spyro, Ape Escape, R&C and J&D