Lenovo has started rolling out Android 6.0 Marshmallow update for the Vibe S1 in India and the UAE. Although quite slow with Marshmallow rollout, Lenovo has recently been very active with the A7000, K3 Note and Vibe P1 already getting their share of the latest Android updates.
The update OTA file is about 1.6GB in size and should only be downloaded over WiFi. The same recommendations remain here as well with the Marshmallow update. If you have switched the default write disk to SD card, all apps/data moved to the SD card will not be accessible. You need to move them back to the internal storage.
The update will take quite some time to install and there will be quite a number of restarts before the Marshmallow update finally installs on your Vibe S1. There are a lot of new things coming your way with the update including Google Now on Tap, better performance, battery life with Doze Mode, new permissions management and a lot more.
Do tell us your experience with the Marshmallow update on the Vibe S1 in the comments section, especially if you find something new and interesting.