diff --git a/resources/private/worker.js b/resources/private/worker.js
index 48530fb..ffec69e 100644
--- a/resources/private/worker.js
+++ b/resources/private/worker.js
@@ -1,7 +1,8 @@
 const relatedAppVersion = '1'; // prop:relatedAppVersion
 const urlsToCache = ["/", "index.html", "js/app.js", "css/styles.css", "img/icon.svg", "manifest.json"]; // prop:urlsToCache
 
-const cacheKey = `resources.${relatedAppVersion}`;
+const cacheKeyPrefix = 'nenadalm.life-counter.';
+const cacheKey = `${cacheKeyPrefix}.resources.${relatedAppVersion}`;
 
 function ensureHtmlVersionMatches(cache) {
     return cache.match(new Request('index.html'))
@@ -23,6 +24,7 @@ self.addEventListener('install', event => {
 self.addEventListener('activate', event => {
     event.waitUntil(
         caches.keys()
+            .then(keys => keys.filter(key => key.startsWith(cacheKeyPrefix)))
             .then(keys => keys.filter(key => key !== cacheKey))
             .then(oldKeys => Promise.all(oldKeys.map(key => caches.delete(key))))
     );