[Galaxy A3, A5, A7, A8, A9 General] onimorza:
You don't need to do the complicated process of deodexing your ROM yourself or installing a deodexed Android 5.0 Touchwiz ROM any more prior to installing xposed on our A-series now!

I am however not responsible if you brick your phone; please know the risks of continuing.

Note: this is for Samsung 5.0 Touchwiz only as based on arter97's thread [UNOFFICIAL] Xposed for Samsung Lollipop by arter97!

For 5.1 & 6 please go to Wanam's thread [UNOFFICIAL][5.1.1/6]Xposed for Samsung Lollipop/Marshmallow.

For non Samsung Touchwiz, go to rovo89's thread [OFFICIAL] Xposed for Lollipop/Marshmallow [Android 5.0/5.1/6.0].

For older versions I have no clue, please search the xposed general section.

Warning, this installation needs like 500MB on your system partition to do the conversion (below installation overwrites the system Odex files etc).

Debloat your system partition if necessary! This is really important, otherwise you'll end up in a boot loop!

You can do this with for example GS4 Lollipop Debloat which also works on our devices and SD Maid (thanks to Twiq for this tip in his post)

Debloating is now optional thanks to dkcldark, but it still doesn't harm to clear up some space and get rid of some apps you don't need.

As always, backup everything first, and you might want to have your original ROM zip ready to flash with Odin just in case of.

There is 2 possibilities to get it, one if you don't mind knox counter going up and another one if you want it to stay at 0x0.

Option 1:

knox 0x1, warranty void

This is the easiest one.

Root your device if you haven't done already. Kingroot works great!

If you haven't installed a custom recovery, do so; search the General section of our devices forum to search the TWRP that fits your particular device. Note: I've read that TWRP 3 might cause some issues, so might be better to have version 2. This was at the time of writing; issues might be solved by the time you read this.

Install the xposed installer from this thread. I used XposedInstaller_3.0-alpha4.apk.

Flash xposed bridge from this post through your custom recovery (make sure you have enough space on your system partition, see above). At the moment of writing it was xposed-v79-samsung-test.zip dkcldark's update to v85; download his .zip file from his post here to your phone. This one isn't yet mentioned in the OP as it's a test version.

Clean cache & dalvik.

Reboot. First reboot may take a while.

But after that, xposed is installed!

If everything worked, please report back to arter97's post with a screenshot of Xposed Installer -> Framework with your model number and firmware version as described in his post. And while you're there, buy him a beer! This will benefit future development.

Option 2:

knox 0x0, warranty ok

This one is a bit more complicated as it won't use a custom recovery (which triggers knox).

Root your device if you haven't done already. Kingroot works great!

But Kingroot can't work together with an app we need below, FlashFire, so we need to transform it to SuperSU. Install Super-Sume Pro from Play Store.

Follow on screen instructions of Super-Sume Pro to get SuperSU working.

Mr.W0lf has an alternative option to replace Kingroot by SuperSU through Terminal Emulator here and here (I haven't tested this myself though, so read the complete thread and do research!).

Install the xposed installer from this thread. I used XposedInstaller_3.0-alpha4.apk.

Install FlashFire from Play Store

As FlashFire has some issues with setting permissions of the odex files from the test version of arter97 right, MatrixDJ96 has created a zip which sets the permissions right in this post. Download this xposed-v79-samsung-test-matrixdj96.zip on your phone. dkcldark created an update to v85 with MatrixDJ96's FlashFire fix included; download his .zip file from his post here to your phone.

Open FlashFire, click on the "+"sign, select Flash ZIP or OTA and select the zip file you just downloaded. Continue in next screen; click the "+"sign again and select Wipe. Only select Dalvik cache and Cache partition here and continue.

Go to the bottom of the screen and click on the big Flash button (make sure you have enough space on your system partition, see above).

FlashFire will reboot the phone and start doing it's magic; this might take a while, and first boot too.

But after that, xposed is installed! And you still have your waranty on your phone!

If everything worked, please report back to arter97's post with a screenshot of Xposed Installer -> Framework with your model number and firmware version as described in his post. And while you're there, buy him a beer! This will benefit future development.

In case of.. :

xposed installer saying the framexork is not active:

Thanks to:

[MENTION=4546441]Twiq[/MENTION] for the debloating tips

[MENTION=4419114]rovo89[/MENTION] for xposed

[MENTION=4898097]arter97[/MENTION] for the xposed bridge for our TouchWiz ROMs

[MENTION=4944549]MatrixDJ96[/MENTION] for the xposed bridge for FlashFire

[MENTION=2715309]dkcldark[/MENTION] for the update to v80.1 with FlashFire fix included

[MENTION=631273]Chainfire[/MENTION] for FlashFire and SuperSU

[MENTION=3178012]gatesjunior[/MENTION] for Super Sume Pro

[MENTION=5154981]Mr.W0lf[/MENTION] for alternative to replace Kinguser