commit 96f271e9b77401eac0db9cf564784474a58c749d
Author: Leszek Koltunski <leszek@koltunski.pl>
Date:   Tue Apr 17 22:19:15 2018 +0100

    Minor.

diff --git a/build.gradle b/build.gradle
index 31ba2b8..fcc9b5c 100644
--- a/build.gradle
+++ b/build.gradle
@@ -4,7 +4,7 @@ android {
     compileSdkVersion 27
 
     defaultConfig {
-        minSdkVersion 18
+        minSdkVersion 21
         targetSdkVersion 27
     }