Re-write F-droid paragraph

supporting-docs/guides/2015-08-19-faq.md

@@ -574,15 +574,11 @@ built by [Jenkins](http://matrix.org/jenkins/job/VectorAndroidDevelop). Use it a
 
 ##### I installed Vector via F-Droid, why is it draining my battery?
 
-The F-Droid release of Vector does not use [Google Cloud Messaging](https://developers.google.com/cloud-messaging/). Which allows users that do not have Google Services installed to use Vector.
+The F-Droid release of Vector does not use [Google Cloud Messaging](https://developers.google.com/cloud-messaging/). This allows users that do not have or want Google Services installed to use Vector.
 
-The drawback is, that Vector has to pull for new messages, which can drain your battery.
+The drawback is that Vector has to pull for new messages, which can drain your battery. To counter this, you can change the delay between polls in the settings. Higher delay means better battery life (but may delay receiving messages). You can also disable the background sync entirely (which means that you won't get any notifications at all).
 
-You can change the delay between two polls in the settings. If you chose a higher delay you battery life should improve.
+If you don't mind using Google Services, you might be better off installing the [Google Play store](https://play.google.com/store/apps/details?id=im.vector.alpha) version.
-
-You can also disable the background sync entirely (which means that you won't get any notifications).
-
-If you are not happy with that, just install it from the [Google Play store](https://play.google.com/store/apps/details?id=im.vector.alpha).
 
 ##### Where can I find a web app?