Bugfix key validation

app/src/providers/crypto/crypto.ts

@@ -159,7 +159,7 @@ export class CryptoProvider {
 
   public async isPrivateKeySet(): Promise<boolean> {
     const privateKey = await this.storage.get("privateKey");
-    return privateKey.length > 0;
+    return privateKey;
   }
 
   public encrypt(plainText: string, privateKey: string) {