The phone in the movie was a Nokia. I believe it was the 7910, if memory serves me correctly.
The spring loaded slide wasn’t really a thing. I think one version of the phone had it in the production release, but it was limited to a very small geographical area… I think somewhere in Asia? I forget.
Everywhere else had the phone to some extent, minus the spring loaded sliding action. You just had up push the cover down.
Source: my best friend had one. After… I think, 3? Years of owning it, he was so fed up with its dumb quirks that I think he snapped the slider thing off… Which had the mic in it, so he got a new phone right after that.