All five SimX modules run inside the SimX Super Applet — from under 30 KB for one module to ~35 KB for the full suite — managed by one platform. Modules ship dormant: enable any mix at rollout or later, remotely, without touching the SIM again.
Adding a capability later is a configuration change, not a SIM replacement program. Start with the module that solves today's problem; the rest are already on the card.
Start with the module that solves today's problem.