This tutorial will teach you how to install CyanogenMod 13 Android 6.0 Marshmallow on your Samsung Galaxy S5 device. This version allows you to port the latest version of Android, Android 6.0 Marshmallow to your Samsung Galaxy S5. There is also a tutorial to Install Samsung Galaxy S6 CM13 Android 6.0 Marshmallow. The first devices to run Android 6.0 Marshmallow are the Nexus 5X and Nexus 6P. In other words, for the many previously released Android devices, there won’t be an Android 6.0 Marshmallow update for quite some time (and there is no guarantee that your device will get updated). You can, however, choose to wait for Samsung to release Android 6.0 Marshmallow for the Samsung Galaxy S5 OR you can get Android 6.0 Marshmallow on your Galaxy S5 via the CM13 ROM developed by albinoman887’s over at xda.
In order to install CM13 on your Samsung Galaxy S5 you first need to download the CM13 ROM and simply flash it using a custom recovery like TWRP or Cyanogen recovery (which is available for most devices) with a factory reset/wipe data. he necessary downloads are available for you below. Before you continue, you should note that you would be required to download and install the necessary Gapps package for your version of Android. Currently we have a Gapps 5.1 Lollipop Download page but for this ROM you will need the Gapps 6.0 Marshmallow Download.
The Galaxy S5 CM13 ROM is available for all GSM variants of the S5 running on Qualcomm processor. This includes AT&T S5 G900A, T-Mobile S5 G900T and other klte variants of the device (G900F, etc).
Those are the two most important set of files that you need right now and I assume that you've already installed a custom recovery... you wouldn't be reading this if you don't know how to do that, would you? But if you don't have em already, here are the instructions for installing the TWRP recovery on the S5. Once you have all of these prerequisites, move to the next page to learn about the installation process.
That's all there is to it. If everything went well, your device will now boot and you will be welcomed by the Android 6.0 Marshmallow setup page. Thanks for reading how to install Android 6.0 Marshmallow cyanogenmod 13 on Samsung Galaxy S5 and I hope that this tutorial has helped you.