In order to provide the best user experience you only need to encode into the QR code a simple URI with the crypto address inside.
The simplest way to create a QR code is to use Google Chart Service. It is a special service that generates universal QR codes and has a very simple API to manage it. According to the request parameters, the QR code will contain the necessary data and it will have defined size dimensions.
A minimum set of parameters is: chs - chart image size cht - chart type ("qr" is necessary for QR code) chl - the data encoded in your QR code choe - encoding type of the QR code data
Detailed description can be found here:
In order to create the QR code you can use Google Chart Service and encode the URI described in What is a crypto wallet URI format? Section.
To create simple QR codes including the link to the bitcoin address the following parameters should be used:
chs - QR code size ("150x150" size is used as an example)
cht - chart type ("qr" is necessary for QR code)
chl - the data encoded in the QR code ("bitcoin:3AFaCnqriLNxj15kqtp5Pxn8puHfuqbX7W" has been used in the example above, but additional parameters can be used according to "BIP-0021" standard documentation: https://github.com/bitcoin/bips/blob/master/bip-0021.mediawiki)
choe - the encoding type of the QR code data ("UTF-8" is required by "BIP-0021" standard)
When the user scans this QR code they will be able to open the wallet application and to make the deposit in one click.