The first synthesizers were so big that they took up entire rooms at universities. Later, they became portable because someone figured a way to load them onto railcars.
By the end of the 60s, they were the size of a desk, which made them more manageable but were still a bitch to program. It took another fifteen years before they were small enough, powerful enough, coherent enough, and cheap enough for the average musician to afford one.
Anyone who grew up in the analogue/early polyphonic synth days will look on this new app as something akin to magic and sorcery.
The AudioKit Synth One is a free open-source iPad app that can turn anyone with the right level of curiosity into Kraftwerk. Just look.