[Oppo R819] distan7:
Modding partition for MT6589 involves hex-editing two files EBR1 and EBR2 which you can find in ROMs that can be flashed using SP Flash Tool. Editing these files is easy, you only need to change a few things and flash them. Finding such ROM, in other way, is not so easy for this phone.

What I share here is a Aroma Installer file you must flash in TWRP (Did not work on Oppo recovery so please don't ask). Install / flash the zip file just like flashing ROMs and it will start-up a GUI and you just follow the instructions.

First, for the sake of common understanding let's agree with these terms below so you'll know what I mean when I said SD Card or Internal etc.

Phone Storage / SD Card : This is where you keep your music, photo, video, downloaded files etc.

System Storage / Internal : This is where your phone stores installed apps with their data, dalvik files etc.

Oppo ROM : Old default ROM in R819 before official ColorOS (green bootlogo).

ColorOS : The current official ROM for R819 (silver bootlogo)

Stock ROM / AOSP ROM for R819. Some refer this to Stock ROM, some say AOSP ROM.

Now here are the steps to do this. Looks complicated and advanced ? Well maybe, but not until you try them.

A. Root your device (skip if you're rooted already)

You can do this with simply running an application called Framaroot. Thread at xda-dev here. Choose the latest version, or you can just donwload Framaroot-1.8.1.apk

Install Framaroot then open Framaroot

Choose Install SuperSU and tap on Boromir. You can also try with Faramir (it depends on Framaroot version)

If you see a message saying "Success" then you're rooted. Just reboot your device.

If Framaroot suddenly closed with no message, just simply re-open Framaroot and re-do the Rooting Process

B. Flash TWRP Recovery & Nandroid Backup (skip if you have done this already)

We'll need TWRP Recovery to do this process.

Download TWRP recovery first. Thread at xda-dev here or you can just download openrecovery-twrp-2.6.3.0-R819.img.

Open Google Play and install Mobile Uncle Tools

Flash TWRP using Mobile Uncle Tools :

put the downloaded openrecovery-twrp-2.6.3.0-R819.img in root folder of your SD Card

Open Mobile Uncle Tools

Choose recovery update

Choose openrecovery-twrp-2.6.3.0-R819.img (it should be on top of the list)

Reboot into recovery and see if you can see TWRP

Make Nandroid Backup

Reboot back to system.

C. Backup, backup, backup

You need to make backup, many kind of backups. Nandroid backups, Application Backup and also your entire SD Card backup.

If you're using ColorOS you can use built-in app called "Backup & Restore". It make backup of your contacts, messages, MMS, call logs, Calendar, Clock (and alarm), Weather, Settings and Theme. It also make backups of your user installed apps and data. Or maybe you have the all powerful Titanium Backup or Helium or other kind of apps that can do backup, please do so. Make backups.

Connect your device to PC and make backup of your SD Card. Everything. This SD Card partition will get resized and needs to be formatted. So this means you'll have a copy of your Backup you made using Application, and Nandroid backup made by TWRP.

D. It's Flashing Time

You're rooted, twrp-ed and backed-up. Now it's time for flashing

Download OPPO-R819-ReParted-v1.5-by_Distan7.zip and copy to your SD Card.

Boot into recovery (TWRP). If you find this hard to do, just open Google Play and download Quick Boot and open it.

In TWRP, tap Install, choose my mod zip file and follow the instructions. You can choose between five partitions size for your Internal storage : 1 GB (Factory Default), 2 GB (recommended), 2.5 GB (my current settings), 3 GB and 3.5 GB. Don't ask about 4 GB please.

After installation, don't forget to Wipe SD Card. Remember SD Card gets partitioned and needs to be formatted. If during boot there's a message about encryption or storage needs repair, just go to settings and find Factory Reset.

Oh by the way, I did tell you to backup stuffs before you start the installer, right ?

E. Restore

Why do you make backups ? So you can restore stuffs. Here are some reading for restoring data :

Your SD Card is now around 1 GB to 2 GB smaller in size, so don't get confused when your data won't fit into your SD Card as it used to.

Restoring Nandroid Backup in TWRP works for me, but some users said they had problem with Google Apps sync after nandroid restore. I don't know if it's related to my mod or not.

You can restore from your backup made in "Backup & Restore" or using Titanium Backup or else.

Don't forget to check your APN, sound settings, bluetooth pairing, WiFi etc.

Small talks

I tried this many, many times, testing the partition result and also the installer. I was about to release EBR1 and EBR2 to be flashed with Flash Tool, but I remember that Meteos APK and ReParted could also flash EBR files. I don't understand anything in Meteos smalife file while ReParted makes more sense. It basically edify updater-script executed under Aroma installer.

I also found out that if you don't have any apps installed on SD Card before installing this mod, there's a good chance you don't have to do a factory reset. All my apps are installed at internal, and flashing this mod many times with different sizes and I didn't have to restore a single app or settings. But SD Card do need to be formatted.

Oh by the way, please leave feedback in the forum so we all can learn too.

Change logs :

2014-01-05 : v1.5 - Add 2.5 GB and 3.5 GB mod

2014-01-04 : v1 - 2 GB and 3 GB mod

Credits :

1. ReParted script is authored by Xakep from lenovo-forums.ru

2. Aroma Installer for ReParted is modified by rainextra

3. Aroma Installer itself is created by Amarullz

4. Mod 2GB, 2.5GB, 3GB and 3.5GB is made by myself