Patch from origin repo:

49dea51 Luke Inman-Semerau on 26.10.15 at 20:56 (committed on 26.10.15 at 22:20)
actually uninstall... adb install -r doesn't seem to actually work all the time.

Fixes #994

Author: sourakov

changelog.md

@@ -1,6 +1,6 @@
-0.18.0-SNAPSHOT (under current development)
----
-
+0.17.1
+-------------------
+- uninstall before installing, since adb install -r doesn't appear to work correctly all the time [#994](../../issues/994)
 
 0.17.0
 ---

selendroid-standalone/src/main/java/io/selendroid/standalone/android/impl/AbstractDevice.java

@@ -127,8 +127,13 @@ public boolean isInstalled(AndroidApp app) throws AndroidSdkException {
 
   @Override
   public void install(AndroidApp app) throws AndroidSdkException {
-    // Reinstall if already installed, Install otherwise
-    CommandLine command = adbCommand("install", "-r", app.getAbsolutePath());
+    // Uninstall if already installed
+    if (isInstalled(app)) {
+      uninstall(app);
+    }
+    // -r: replace existing application
+    // -d: allow version code downgrade
+    CommandLine command = adbCommand("install", "-rd", app.getAbsolutePath());
 
     String out = executeCommandQuietly(command, COMMAND_TIMEOUT * 6);
     try {