I know it's funny thing but you have to make sure to to teach these common things first,if your grandmother or grandfather or elder who are using keypad mobiles or land phones they doesn't know how to call of you buy him/her a smartphone you have to show how to use the mobile and the first thing you have to teach them how to make a phone call to someone in smartphone,show them how to unlock phone and call through dial pad,it's very important if you left your elder him/her alone if they want to call you in urgent if they doesn't know even how to call when they need using smartphone then there's no use of buying smartphone,everyone can't learn everything at a time give them a time to learn cause it takes time to learn by them,when they are enough to get know how to call others now teach them how to answer a call by calling from your mobile to their smartphone,Now move on to next step.

Let them know how to play videos and songs present on your mobile now teach them how to play videos by going to media player that present on your smartphone there are also many different video player apps were present in store you can also install them and teach them how to find and open the media player app and how to play videos,you can teach them how to play songs present on smartphone by using music application teach them how to find and open music app and how to find a particular song to play it's quite easy and they can easily learn,Now move on to next step.

Show them boy to search in YouTube for their needed video or what they want to see beacause youtube is the place we get all songs and videos and whatever information we needed with visuals, youtube can really help them to pass time easily when they get bored,Now move on to next step 

It takes time to learn them how to use Browser show them with some examples how to search like if they need to know what to in an special particular day then show them by searching what to do in that day or event with typing in search box and read posts they needed,once they learn how to use Browser it's easy for them to search what they need for and read,Now move on to next step.

Let them know how to install apps from store it's very easy all they have to do is just remember store to install an new app show them how to search and install particular app,some apps may shows ads in between app while using it they will accidentally click on it and they went for someother page so let them know what are add and how to close ads and use app,while they using browser or any app they accidentally click in ads and install apps from playstore these were unwanted so teach them how to uninstall unwanted apps it's quite easy it can be done by long press on app and click on uninstall,Now move on to next step.

It's very important to teach them how to download their needed images and videos from online,let them teach how to search and download images and videos they needed by search online there are also many apps which makes them easy to search download without any struggle and later they can watch in their free time,teach them to remember some sites in online where they can download all videos stuff easily,however images can easily download by searching in google search box and then move to images from top below search box, Now move on to next step.

Everyone use social media accounts like facebook,twitter, Pinterest....etc where they can find great stuff and get know daily updates and Videos,so take your time to create accounts for them by you and make log in in particular apps and teach them how to use and message to their loved ones,and make video calls,you can also teach how to post their photos in special occasions and greetings to all relatives in a particular day,Now move on to next step

As we know now days we daily read and see news upon virus target and many scams by frauds which makes people losing their money from bank accounts by sharing secure details like credit card,debit card and bank account details or otp,give proper information to them how frauds scam your money through online and give them idea not to share any personal information on calls and text,because the scammers will easily target elders and scam money from them,Now move on to next step.

There are many online Banking apps are present you have to create an account for them and after all setup tell them their password number or transaction password,now show them how to enter into app and how to send money through upi or by entering bank account details,you can also teach them how to check their balance and who sended money to their account,make sure to guide them with full details beacuse it's high sensitive issue there may be chance to send money other people's with mistake values or entry.

Finally it's the last thing was patience don't get angry on them if they do any mistake while learning cause it's time consuming process and everyone should have to start from nothing to know something but it takes time give them time and let they learn how to use if you teach all above steps and now I'm sure your work had completed