Best way to connect iPad to integrated amp

Stereo5 is correct you need the adapter. They have one that allows you to skip the need for a usb hub and use it with your charger.

For just about the same money as the cable you can get a Klipsch Gate off of Amazon and use your ipad to control the Gate around $30 shipped. 

The sound quality is fantastic and I prefer it over the Bluesound Node 2i I had. 

Before the Node (ive had the node 2 and 2i) I was using an ipad as a streamer with the dacs in a Hegel h160, Outlaw rr2160, Peachtree Nova 150, Centrance Dacmini, Devilsound HD, Jolida Glass and a few others but was not happy with the sound. 

For the price and option to return it you can’t go wrong. 

https://www.amazon.com/AmazonBasics-3-5mm-2-Male-Adapter-Cable/dp/B01D5H8JW0
3.5 mm  to  RCA  adaptor
From the earphone output of the Ipad to the preamp.

but I not shure about the sound quality

I have seen the 3.5 to rca stuff. I was trying to find out if there is a dac/ streamer that bypasses the iPads internal processing. I don’t believe the sound coming out of the headphone jack will be all that great

https://www.wifihifi.ca/LatestNewsHeadlines/Hands-OnReview:AudioQuestDragonFlyBlack1.5/Red.html

Ipad / iPhone to APPLE  camera adapter
Then camera adapter USB to AQ Dragonfly mini-DAC headphone amp USB 
then output from AQ 3.5mm mini to RCA (L-R) analogue cable.

i have both the AUDIOQUEST FOREST and WIREWORLD cables....the WIREWORLD is a whole step up in performance.
I use the AQ for my system above with mobile headphones but the WW for my connection to my B system integrated amp

https://www.whathifi.com/chord/hugo-2/review

I think you will have to go the APTX ( bluetooth )  way to get music out of your Ipad with a good sound quality.