Welcome to my Website! // About Maxr1998

Hey there! I'm Max Rumpf, a 21-year old student & hobbyist Android developer acting under the pseudonyme Maxr1998. I am Recognized Developer and Contributor on
In my free-time, I create apps and mods for powerusers, like MaxLock, an applocker, or HassDroid, a client for the Home Assistant home automation platform. View a list of my projects here.
I'm also active on various other sites, check out the links below. You can contact me via Telegram, as specified below.

My GPG key: 11CDF7B8

My stuff

Hardware & Software I use, like and recommend:

  • Dell XPS 13 9360, i7-7560U, 16GB of RAM (powerful, well-built & good-looking device, with an insanely good screen and battery life)
  • Arch Linux, on the above laptop
  • i3wm, a fast and powerful window manager once you learn it - Link to my current config
  • fish (much smarter auto-completion than bash, and a lot of cool additional features)
  • Vim, link to my config (I never thought I'd actually use this one day. I don't even now recommend anyone to use it, if you don't want to spend hours learning and configuring a *file editor*, but if you master it, it's FAST)



  • German: natively
  • English: very well (Camebridge English: Advanced certificate, CEFR level C1)
  • French: ok (DELF certificate, CEFR level B1)

Software experience/programming languages

  • Android (Kotlin/Java)
  • Linux, shell scripting and server management
  • Web development (Ktor, Go, node.js, Tomcat, Django, WebGL)
  • Telegram bots and command line apps in Go
  • C, RISC-V Assembler (in University)
  • Docker (because containers rule™)
  • First experiences in Haskell (workshop) and Fortran
  • Lua (ComputerCraft coding)
  • Atlassian stack (for the CampusApp of Augsburg University)
  • See my GitHub for more…

Apps & Projects

MaxLock is an applocker for Android, that features a powerful Xposed implementation as well as a no-root accessibility service one to protect your apps with a lockscreen.

HassDroid - an Android client for Home Assistant

Native Android user interface for the Home Assistant home automation software


A website to view your unique visits from the game Ingress on a map (using leaflet.js), with a Go backend (optionally inside docker) and a JavaScript + WebGL frontend

XGPM [abandoned]

Xposed mod that customizes the look and feel of the Google Play Music application and adds a few extra tweaks.
Not maintained anymore, as I switched to Spotify.

XMediaNotificationTrackSelector [abandoned]

Xposed mod that adds a track selector to MediaStyle and other music notifications on Android 5.0 which either support its custom API or the official MediaSession API with queue and controls. Supported by Google Play Music and Timber.


Android app and linux-pam module which allows you to unlock your PC with your phone's fingerprint reader, using a challenge response verification system with an ECDSA keypair, and the Google Firebase realtime-database for message transfer.
hellsCode is a kernel and system mod that enables unlocking via knock code on the LG Nexus 4 [abandoned]

Android Libraries


Android Preferences UI defined through Kotlin DSL, shown in a RecyclerView


Custom View that allows to select a day of week like in a calendar, written for the CampusApp of my University


Niagara Launcher

Small code contributions and integration of ModernAndroidPreferences

Main author: 8bitPit

Android N-ify

Xposed mod that backports features from Android Nougat to Android Lollipop and Marshmallow!

Contributions: Direct reply, Google Assistant, Partial screenshot, bugfixes, build server and issue management

Main authors: MrWasdennnoch and paphonb

Always On AMOLED

App which makes your device show the time & more when the screen is "off", just like the Galaxy S7!

Contributions: Pocket mode, bug fixes, etc.

Main author: Tomer Rosenfeld

… and even more

More contributions to open source projects are listed as forks on my GitHub


I also helped translating quite a few third-party apps to German, here are some of them:

  • Always On AMOLED
  • Android N-ify
  • hellsCore Kernel Manager
  • MultiROM Manager
  • XDA-Labs