Close apps on Android and setting reminders?

So, I'm new to android phones. I just got an android Lenovo A526. I have searched on the net but could find an option to close the apps running in background. Kindly help me out.

Also can anyone tell if there's an option to set reminders in this phone (without using internet). Should I download a app or is the option built-in.

Sound effects different from other Android smartphones?-Clash Of Clans?

I was playing Clash Of Clans using my smartphone. Then I tried to play Clash Of Clans using my mother's bigger screen smartphone.

I noticed that the game's sound effects was different and better on my mother's smartphone than my smartphone.

Is it possible to solve this problem? If it is possible, how?

My phone is Acer Z130
My mother's phone is Lenovo A850
Both of them have the same Android version (Jelly Bean 4.2.2)

Which mobile should i buy? - 1

Sony xperia c
moto g gen 2
lenovo s850

i want to have a phone with very good camera… Under 15000INR
please give a detailed explanation for your answers.

Lenovo s820 mobile camera?

Lenovo s820 12 megapixel camera is good camera or 12 megapixel is showing but work 8megapixel

Are Lenovo smartphones good or not?

Hey and thank you for your reply in advance!

So I've been reading up on Lenovo phones emerging into the Western market and in my country in mere days and the prices grabbed my attention, the specs seemed good from what I know but I've never owned a smartphone until now.

- Are Lenovo phones good? If not, what problems do they have?
- Any recommendations you would give me, directions into brands, OS or a specific phone?

Is it right for me to have a phone?

I'm a 13 year old, and have an iPad, a Sony Xperia Tipo ( the basic rs 8500 one) and a IPod. I hardly use the iPod, it's basically my fathers old one, not a touch, just for listening songs. I don't like to listen songs in the iPod.
I asked for the phone on my bday last to last year. Mind you I did not get any other gifts except for chocs from every 1( including friends, classmates and relatives, mom said them not to give)
On my 12 bday, mom gave me my iPad mini. I never asked for it.

So now do you think I'm spoilt?!
Should I not use my phone n iPad?! Should I give it back?!

A friend of mine keeps telling me that. She has got quite good parents. They gave her a micro max fun book, Bt she broke it. Then she got a Lenovo tab that too was lost. Her parents now don't trust her, so she only has a hand down android basic smartphone.

So am I really spoiled?! Or she's just being jealous!

Which brand is good in mobiles - lenovo or sony?

I planned to buy Sony but ended up buying lenovo s650 because my friend told that it was looking better than sony. Now I'm feeling sad and wish I could have bought Sony itself.
The mobile is working fine but I just want to know whether it is a good brand.

Should I buy Lenovo A390 smartphone?

I have opportuniy to buy this phone for 60euros($80), used, 7 months old, in warranty till November 2015, well preserved. Should I go for it?

Specs:

Processor 1000mhz
RAM 512
Internal 4GB
Battery 1500
Android 4.0.4
Camera 5mp, no flash, fixed focus.

Whenever I want to post photo on Instagram?

OK, so I have a phone and I want to upload a photo on Instagram, but my phone says "Your SD card is full". I don't even have any pictures on my phone except the one that I want to upload which means only one picture. But I do have 100+ music. I don't think music is the problem. My SD card is 6 GB. My phone type is Lenovo A680.