Samsung Galaxy S was released in 2010 and this is the first galaxy phone.Galaxy S made Samsung very popular in the android community.The phone has a great dev support.That’s the reason after more than 5 years, still the device is getting latest ROMs.The device has been receiving unofficial Android jellybean, Kitkat, lollipop and now Android 6.0 Marshmallow. This Omni Marshmallow ROM is in Alpha stage.It is not stable and we don’t recommend users to use it as a daily driver. However, if you like to test Android 6.o Marshmallow  on your Galaxy S I9000 than this is the best way to do it. This Omni ROM is developed By sooti, Senior Member from Xda.this is the first release of the ROM so there will be bugs but we are sure in future updates everything will be fixed.Below we share bugs list

Working:

RIL Wifi BT Sensors Camera (use third party such as open camera Internal SD (using data partition for now since we need to add a commit to emulate the full storage partition) Audio + vibrate buttons (except home to wake, I need to add that but it does go to home screen, just use power to wake for now) USB storage (Make sure you disable debug mode when you use it since it causes issues mounting it sometimes)

Not Working:

GPS (need to update something in the blob apparently for 6.0) SELINUX (disabled for now until I add permissions but its low on my priority right now) tons of smaller things, feel free to comment about device issues so I can add it (Omni stuff don’t count, so please don’t add those, instead open a bug with them)

→ For More details on this ROM and updated Bug list visit this Official Xda Post Now it’s Time to Flash / Install Android Marshmallow On Samsung Galaxy S I9000 via OmniROM

Warning:

rootmygalaxy.net will not be held responsible for any kind of damage occurred to your Galaxy S while following this tutorial.Do it at your own risk.

Pre-Requirements:

Only for Samsung Galaxy S I9000 Make Sure your device is rooted and you have latest CWM recovery Installed on your device First boot into recovery and take a nandroid backup (Important) As said earlier, this is an alpha build, so we don’t recommend to use this as daily driver.

Follow the guide below to download & Install Android Marshmallow On Samsung Galaxy S I9000 via OmniROM

Download

Omni-6.0-20151201-galaxysmtd-HOMEMADE.zip (ROM) Check out the official Xda post for more info Marshmallow Gapps — Link 

How to Flash / Install Android Marshmallow On Samsung Galaxy S I9000 via OmniROM

Step By Step Guide

First of all, read Pre-requirement Section Now download the ROM file and Gapps pack from the download section above Now connect your device to PC via USB cable Then transfer both downloaded files to internal memory of your device Now boot your device into CWM recovery.To Do So turn off your device completely, now turn it on by pressing and holding Volume Up+Home Button+Power Key, you will see the CWM interface now. Once you are in CWM recovery, wipe factory and cache Now Install / Flash the ROM.To Do So Select “Install Zip > Choose Zip from Sd/Ext Sd > Select the Omni ROM.zip file” Then Select “Yes” to begin the Flashing process. After the ROM Installation is completed Install  / Flash the Gapps (same Process) Once Flashing is done, reboot your device Remember the First fresh boot will take some time may be up to 10minutes.So don’t panic.Detailed guide to Flash / Install the ROM > How To Install A Custom ROM Via Recovery On Any Android Done!!! Now Your Galaxy S I9000 should be running latest android Marshmallow 6.0 (Omni ROM).Check the setting-> ab0ut phone for confirmation

→ In case the boot screen is stuck on the boot logo (bootloop), boot into CWM recovery and wipe cache and dalvik cache, reboot and it should take you into the home screen. Hope this guide will help you.If you have any queries related to this post feel free to ask in the comment section below.We will be happy to help. Via Xda

 Steps  Install Android Marshmallow 6 0 On Galaxy S I9000 - 42