diff --git a/README.md b/README.md
new file mode 100644
index 0000000..8efaaaa
--- /dev/null
+++ b/README.md
@@ -0,0 +1,24 @@
+# HRM
+
+An example heart rate monitor app for Android and MacOS using [git.wow.st/gmp/ble](https://git.wow.st/gmp/ble) and [Gio](https://gioui.org).
+
+## MacOS:
+
+```
+go get git.wow.st/gmp/hrm
+cd ~/go/src/git.wow.st/gmp/hrm
+go build
+./hrm
+```
+
+## Android:
+
+The `gogio` command from `gioui.org/cmd/gogio` must be installed to build
+an Android APK.
+
+```
+go get git.wow.st/gmp/hrm
+cd ~/go/src/git.wow.st/gmp/hrm
+gogio -target android .
+adb install -r hrm.apk
+```
diff --git a/go.mod b/go.mod
index adf081a..4b15559 100644
--- a/go.mod
+++ b/go.mod
@@ -4,6 +4,6 @@ go 1.13
 
 require (
 	gioui.org v0.0.0-20191126175243-2ca2e5462f16
-	git.wow.st/gmp/ble v0.0.0-20191127164604-2af636b9461a
+	git.wow.st/gmp/ble v0.0.0-20191204222510-e7f82ac9e7f9
 	gopkg.in/yaml.v2 v2.2.7
 )
diff --git a/go.sum b/go.sum
index 10c8433..0de98bc 100644
--- a/go.sum
+++ b/go.sum
@@ -3,6 +3,8 @@ gioui.org v0.0.0-20191126175243-2ca2e5462f16 h1:p31rtmKm51xpj2QtqGNlljAyHEP1oStU
 gioui.org v0.0.0-20191126175243-2ca2e5462f16/go.mod h1:KqFFi2Dq5gYA3FJ0sDOt8OBXoMsuxMtE8v2f0JExXAY=
 git.wow.st/gmp/ble v0.0.0-20191127164604-2af636b9461a h1:Nr6kwAliHs2EsGv4Q1EgQACfbb/hVnTYq0CkWfqIj+g=
 git.wow.st/gmp/ble v0.0.0-20191127164604-2af636b9461a/go.mod h1:Fh9BYe6AckJS7dzv2LFPr/wSYVMROUwmtc01VyQmuZo=
+git.wow.st/gmp/ble v0.0.0-20191204222510-e7f82ac9e7f9 h1:IfBmZRWVb0CfjjiSDStqblKMGSwCkGVewkpOuzl+lGY=
+git.wow.st/gmp/ble v0.0.0-20191204222510-e7f82ac9e7f9/go.mod h1:Fh9BYe6AckJS7dzv2LFPr/wSYVMROUwmtc01VyQmuZo=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
 github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1/go.mod h1:vR7hzQXu2zJy9AVAgeJqvqgH9Q5CA+iKCZ2gyEVpxRU=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=