I have two desktop amps that I use my Sundara with(and a portable too). IMO Sundara loves some power thrown it’s way. Try to get Zen DAC+AMP they will be good.
My setup:-
Desktop:-
Topping E30+Cayin HA-1A MK2 Tube AMP/ Topping E30+Anode Acoustics No4 Solid-State Amp(Anode acoustics is an Indian brand).
Portable: xDuoo XD-05 Bal.
Love sundara the most with my Anode No4 amplifier.
Wait do iPads even work with usb DACs?
Also I said I would try plugging my amp (Liquid Spark) straight to the 3.5mm jack of my PC to see if it sounds good without an external DAC. There is definitely a difference in my case but it is very doable.
So you could start either way. 1 get a DAC/AMP (all in one) to start and if (when) you get curious/paranoid you get a more powerful AMP to stack it up.
2. Get a decent AMP to start and if (when) you get curious/paranoid get a decent DAC to stack it up.
If you think you will never upgrade from this (think again if you are reading this forum…) then best way is to get the all-in-one and be done with it.
Either way make sure to read or watch a couple of decent reviews to make sure you know what you are buying and never go with something just because it is hyped right now.
Good Luck!!! 
Man, I really don’t want to get into this hobby, because I can see that it’s a really deep (and expensive) rabbit hole 
As I understand it, Lighting can do just about everything that USB can. I will double check though.
Thank you very much for the help!
I use the USB-C digital AV multiport adapter and I works for my dac. Are there some iPads that use lightening for charging? Older models maybe? I’m running a 7th generation and it’s USB type c. But I also know they called their display port thunderbolt so it’s probably just internal apple jargon
Thanks for including the Zen DAC V2 in your thoughts - it would be a great fit for your sundaras!
Planars like the Sundara can always use a lot of power. The Topping DX3 Pro Plus is in that price range and has a really good DAC and 3,5W of power