Essential Apps for Android
Several useful and free apps are available to make your mobile a personalised device
So you have bought yourself a brand new Android mobile handset and are set to explore its features. Although all mobile handsets do have pre-installed apps for most of the features, they are inadequate. For example, there is an in-built video player in every smartphone, but it does not give options to control playback, resume or zoom. Therefore, you need to get a free app, like MX Player or VLC Player, from the apps store or buy its paid version. Assuming that you are using a new Android handset, here are some of the essential, and feature-rich apps, for everyday usage:
1. Anti-virus: The two free apps mentioned below are listed as top grossing in Google Play. Since both do their job as the name suggests, there is no need to buy an anti-virus app by paying a few hundred rupees.
a. Avast Antivirus & Security: This is probably one of the best anti-virus apps that also offers anti-theft solution. 
b. Kaspersky Internet Security: This app offers anti-virus protection as well as anti-theft protection.
2. Backup & Restore: This is used for taking a backup of your installed apps, contacts, call logs and SMSs (short messages). Data in WhatsApp can be archived or emailed so there is no need to use external apps for it. 
a. Apps Backup: When it comes to backup of your installed apps, nothing works like ‘App Backup & Restore’. More than 10 million users have downloaded this small (3.62MB) utility—one of the more easy and simple utilities on which you can back up your installed apps and restore (reinstall), if required. 
b. Contacts/Call Logs/SMS Backup: 
i. Avast Mobile Backup & Restore is one of the good free utility apps that allows you to back up your contacts, call logs, SMSs and photos for free, at predetermined time interval or as per your choice. You can add a PIN (personal identification number) for protection as well. Except photos, all other data is backed up with Avast user account and can be restored.
ii. SMS Backup & Restore, developed by Ritesh Sahu, does what it says. It creates a backup locally or even on email, Google Drive or Dropbox. This can be used to restore your handset after reset or to load SMS data on a new device.
3. Music & Videos: For listening to songs or music, you can either use online services, like Saavn or Gaana, or use apps, like JetAudio Music player+ EQ Basic (more famous for its PC version). I would have liked to add Poweramp also, but its free version is actually a 15-day trial version. With free versions of Saavn and Gaana, you can listen to songs online or create a playlist, but cannot download for which you require a paid version. JetAudio’s free version offers 10-band graphic equaliser and various sound effects, like X-wide, reverb and X-bass. For videos, you can choose VLC media player or MX Player. While VLC is completely free, you can buy a paid (ads-free) version of MX Player. Over 100 million users have downloaded MX Player, while, for VLC, the number is over 50 million. 
4. Personalisation: The biggest advantage of using an Android device is the option to customise its look & feel. It can be achieved by using launcher apps, like Go Launcher, Lucid Launcher and CM Launcher. But most launchers offer few options to do any customisation in their free avataar. All these launcher apps are small in size (less than 6.21MB) but themes that you may want to add for personalisation may make the apps heavy in size. Google Now Launcher and Yahoo Aviate Launcher are two other worthy personalisation apps to note.
TIP: How to activate local language?
You need to disable ‘system language’ as the default option using the keyboard and then add local language (input), like Hindi, Marathi or Kannada. Go to Settings>Language. Check your current keyboard and input method and add any other language, as per your choice. 
Pravesh Pandya
7 years ago
Yogesh, One shouldn't need an antivirus as long as one is on a app-install binge or browses unknown websites. If someone uses a list of well known apps and visits very few websites, anti-virus is not worth the overhead.

Also trusting any backup provider may not be the best option. What if they backup in their own servers?

While different from your suggestions, I generally refer to this list &
Yogesh Sapkale
Replied to Pravesh Pandya comment 7 years ago
Thanks for your comment, Praveshji.
AV turns out to be more useful since most of us, do share photos, videos, songs etc all the time. SO it is better to be safe than sorry.
Secondly, both Apps Backup & Restore and SMS Backup & Restore, save the backup files locally, even on the external microSD card. Avast offer to save it on their server. It up to individual choice whether to store backup locally or on cloud.
Hope this clears your doubt.
Thanks again,
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