diff --git a/TODO.md b/TODO.md
index bef3149c..45e31164 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,9 +1,12 @@
 
+* test reg reading/writing directly via bt to device
 * fix bluetooth update
 * add real messaging code/protobufs
 * use https://codelabs.developers.google.com/codelabs/jetpack-compose-basics/#4 to show service state
 * connect to bluetooth device automatically using minimum power
 
+protoc -I=. --java_out /tmp ./mesh.proto
+
 # Medium priority
 
 * remove secret google settings json before open sourcing
diff --git a/app/build.gradle b/app/build.gradle
index 0ddb520f..603c4263 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -6,6 +6,9 @@ apply plugin: 'com.google.gms.google-services'
 // Apply the Crashlytics Gradle plugin
 apply plugin: 'com.google.firebase.crashlytics'
 
+// protobuf
+apply plugin: 'com.google.protobuf'
+
 android {
     compileSdkVersion 29
     buildToolsVersion "29.0.2"
@@ -41,6 +44,22 @@ android {
     }
 }
 
+// per protobuf-gradle-plugin docs, this is recommended for android
+protobuf {
+    protoc {
+        artifact = 'com.google.protobuf:protoc:3.9.0'
+    }
+    generateProtoTasks {
+        all().each { task ->
+            task.builtins {
+                java {
+                    option "lite"
+                }
+            }
+        }
+    }
+}
+
 dependencies {
     implementation fileTree(dir: 'libs', include: ['*.jar'])
     implementation"org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
@@ -52,6 +71,9 @@ dependencies {
     androidTestImplementation 'androidx.test.ext:junit:1.1.1'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
 
+    // You need to depend on the lite runtime library, not protobuf-java
+    implementation 'com.google.protobuf:protobuf-javalite:3.8.0'
+
     // You also need to include the following Compose toolkit dependencies.
     implementation("androidx.compose:compose-runtime:$compose_version")
     implementation("androidx.ui:ui-framework:$compose_version")
diff --git a/app/src/main/proto/mesh.proto b/app/src/main/proto/mesh.proto
new file mode 100644
index 00000000..87603df3
--- /dev/null
+++ b/app/src/main/proto/mesh.proto
@@ -0,0 +1,29 @@
+syntax = "proto2";
+
+package tutorial;
+
+option java_package = "com.geeksville.meshutil";
+option java_outer_classname = "MeshProtos";
+
+message Person {
+  required string name = 1;
+  required int32 id = 2;
+  optional string email = 3;
+
+  enum PhoneType {
+    MOBILE = 0;
+    HOME = 1;
+    WORK = 2;
+  }
+
+  message PhoneNumber {
+    required string number = 1;
+    optional PhoneType type = 2 [default = HOME];
+  }
+
+  repeated PhoneNumber phones = 4;
+}
+
+message AddressBook {
+  repeated Person people = 1;
+}
\ No newline at end of file
diff --git a/build.gradle b/build.gradle
index 4557f73b..0520b74c 100644
--- a/build.gradle
+++ b/build.gradle
@@ -6,7 +6,7 @@ buildscript {
     repositories {
         google()
         jcenter()
-        
+        mavenCentral()
     }
     dependencies {
         classpath 'com.android.tools.build:gradle:4.0.0-alpha09'
@@ -19,6 +19,9 @@ buildscript {
         // (if not, add it).
         classpath 'com.google.gms:google-services:4.3.3'
         classpath 'com.google.firebase:firebase-crashlytics-gradle:2.0.0-beta01'
+
+        // protobuf plugin - docs here https://github.com/google/protobuf-gradle-plugin
+        classpath 'com.google.protobuf:protobuf-gradle-plugin:0.8.11'
     }
 }