During the first week of April, a lot of Android phones and tablets received the CyanogenMod 13 Nightlies. This brought an upgrade to the existing hardware which is now going to be considered as old hardware.
According to Android Police, CM12.1 was present in most of the devices earlier. These devices faced a small jump, just from Lollipop 5.1 to Marshmallow 6.0. Other devices like the Verizon Galaxy S5 witnessed a huge leap as it had only CM 11 (KitKat) before this update. The new CM 13 nightlies was released for the following devices - Motorola Moto Maxx "quark," Samsung Galaxy S5 (Verizon) "kltevzw," Samsung Galaxy S4 (T-Mobile) "jfltetmo," Galaxy Note 8 (GSM) "n5100" and Galaxy Note 8 (Wi-Fi) "n5110."
A U.S.-based mobile software company, Cyanogen, builds Android-based firmware for mobile devices. CyanogenMod gained popularity after created initially by Steve "Cyanogen" Kondik. It is a custom ROM created for the T-Mobile G1 primarily. Android owners able to load custom firmware on to their device, with CyanogenMod could replace the manufacturer's software experience with CM. It helps gain increased control, a visual style closer to Google's vision of Android, new features and improved boot performance.
CM 13 provides Android with updates like new permissions model (beside the CM features expected by customers) and the battery saving 'doze' functionality. The update is expected to have instabilities and bugs as it is the nightlies. Also, this upgrade is not compatible with third party distributions.
People who have third party distributions have to wipe them off completely before making a switch. It is advised to grab the Marshmallow GApps ZIP package so devices can run Google's services and apps. The CM 13 downloads are available at cyanogenmod downloads. People who love to flash their new ROMs should go for the CM 13 nightly release.