The Android app for Gmail has recently crossed a whopping one billion downloads on Google Play.

Gmail is the first app to reach this significant milestone. The one billion downloads displayed in Google Play Store is a listing of the total unique accounts and not the total number of users that downloaded the app. The one billion unique accounts also contain the dormant and duplicate user accounts.

Also, other famous apps like Facebook, Google Search and YouTube, among others have more active users than Gmail. But Gmail app is pre-installed on most of the Android phones and this helped Gmail accomplish this feat.

Google Play Services crossed the one billion mark way before Gmail, but technically, it is not an app. This service is automatically installed on any device that has Play Store in it and runs on Android version 2.2 or higher. The Play Services comes pre-installed on Android smartphones.

Popular apps like WhatsApp, Google Search, Google Maps, YouTube and Facebook are firmly placed in the five hundred million to one billion ambit. Hence, the next app to cross this milestone could easily be one of these apps.

In addition to this massive feat, Google's Gmail will celebrate its two-year anniversary next month as the "most used email" service. If rumors were true, this could mark the rollout of the significant design change to the users interface, NDTV claimed.

According to leaked screenshots, a new user interface design of Gmail could be in the offing. The ultimate goal of this redesign is to make Gmail's UI look uncluttered.

Aside from the existing tabs like Social, Promotional, Updates and Forums, the new redesign will introduce Travel, Purchases and Finance tabs.

Apart from the altered size and smooth design, the menu on the left side of the inbox has a slide-in pane. The other significant alteration includes the location of "Compose" button that is currently moved to the bottom-right corner. Also, the "Star" option to highlight an important mail is replaced by a "pin."

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