diff --git a/README.md b/README.md
index a60c458d..25cfa388 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,35 @@
-# meshtastic-esp32
+# Meshtastic-esp32
 
-[![Join the chat at https://gitter.im/Meshtastic/community](https://badges.gitter.im/Meshtastic/community.svg)](https://gitter.im/Meshtastic/community?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+This is the device side code for the [meshtastic.org](https://www.meshtastic.org) project.  
 
-You probably don't want this yet.
\ No newline at end of file
+Meshtastic is a project that lets you use
+inexpensive GPS mesh radios as an extensible, super long battery life mesh GPS communicator.  These radios are great for hiking, skiing, paragliding - 
+essentially any hobby where you don't have reliable internet access.  Each member of your private mesh can always see the location and distance of all other
+members and any text messages sent to your group chat.
+
+The radios automatically create a mesh to forward packets as needed, so everyone in the group can receive messages from even the furthest member.  The radios
+will optionally work with your phone, but no phone is required.
+
+Typical time between recharging the radios should be about eight days.
+
+This project is currently pre-alpha, but if you have questions please join our chat: [![Join the chat at https://gitter.im/Meshtastic/community](https://badges.gitter.im/Meshtastic/community.svg)](https://gitter.im/Meshtastic/community?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge).
+
+This software is 100% open source and developed by a group of hobbyist experimenters.  No warranty is provided, if you'd like to improve it - we'd love your help.  Please post in the chat.  
+
+## Meshtastic Android app
+
+The source code for the Meshtastic Android app is [here](https://github.com/geeksville/Meshtastic-Android).
+Soon our first alpha release of will be released here:
+
+[![Download at https://play.google.com/store/apps/details?id=com.geeksville.mesh](https://play.google.com/intl/en_us/badges/static/images/badges/en_badge_web_generic.png)](https://play.google.com/store/apps/details?id=com.geeksville.mesh&referrer=utm_source%3Dgithub%26utm_medium%3Desp32-readme%26utm_campaign%3Dmeshtastic-esp32%2520readme%26anid%3Dadmob&pcampaignid=pcampaignidMKT-Other-global-all-co-prtnr-py-PartBadge-Mar2515-1)
+
+## Build instructions
+
+This project uses the simple PlatformIO build system. You can use the IDE, but for brevity
+in these instructions I describe use of their command line tool.
+
+1. Purchase a suitable radio (about $30 from aliexpress)
+2. Install [PlatformIO](https://platformio.org/).
+3. Download this git repo and cd into it.
+4. pio run -t upload (This command will fetch dependencies, build the project and install it on the board via USB).
+5. Platform IO also installs a very nice VisualStudio Code based IDE, see their tutorial if you'd like to use it.
diff --git a/TODO.md b/TODO.md
index e5f7fd73..ccda621f 100644
--- a/TODO.md
+++ b/TODO.md
@@ -5,6 +5,7 @@ Items to complete before the first alpha release.
 * retest BLE software update for both board types
 * first alpha release, article writeup for hackaday
 * send note about Adafruit Clue
+* send note to the guy who designed the cases
 * send pr https://github.com/ThingPulse/esp8266-oled-ssd1306 to tell them about this project
 
 # Medium priority
@@ -26,10 +27,10 @@ Items to complete before the first beta release.
 * How do avalanche beacons work?  Could this do that as well?  possibly by using beacon mode feature of the RF95?
 * use std::map<NodeInfo*, std::string> in node db
 
-
 # Low power consumption tasks
 General ideas to hit the power draws our spreadsheet predicts.  Do the easy ones before beta, the last 15% can be done after 1.0.
 
+* we currently poll the lora radio from loop(), which is really bad because it means we run loop every 10ms.  Instead have the rf95 driver enqueue received messages from the ISR.
 * platformio sdkconfig CONFIG_PM and turn on modem sleep mode
 * keep cpu 100% in deepsleep until irq from radio wakes it.  Then stay awake for 30 secs to attempt delivery to phone.  
 * have radiohead ISR send messages to RX queue directly, to allow that thread to block until we have something to send
diff --git a/src/screen.cpp b/src/screen.cpp
index d03d34c6..0a3f87fc 100644
--- a/src/screen.cpp
+++ b/src/screen.cpp
@@ -224,7 +224,7 @@ inline double toRadians(double deg)
 }
 
 /**
-     * Computes the bearing in degrees between two points on Earth.
+     * Computes the bearing in degrees between two points on Earth.  Ported from my old Gaggle android app.
      *
      * @param lat1
      * Latitude of the first point