Portable DSD/DAC Headphone Amp for iPhone?

I have Sennheiser HD800 and Beyerdynamic Amiron headphones. What is your recommendation for the best combo DSD/DAC headphone amp out there? I want use my iPhone X as my hi res DSD playback device using the currently installed Onkyo HF Player app. It plays DSD ( .DFF and .DSF) files.  * Must be able to convert at native DSD or hi res PCM (96 /24 or higher) resolution. * Must be truly portable. Ie. Battery powered/chargeable. 
Is there such a plug and play portable converter amp? If so what’s the cat’s meow? Money no object. 


I am a Chord Dealer and Chord makes a couple devices.

For a very good Solution:  

The Mojo is a wonderful portable DAC.  You can connect directly to it with the Apple Camera connector and then plug a USB into it.  The Mojo is $499 and i think the adapter from apple is $99.  

You can also add the Poly to it and stream to it via Airplay or Bluetooth A2DP at redbook resolution.  If you are on a wireless network, you could stream full resolution via WiFi.  The Poly is $649.

For an amazing solution:

The Hugo 2 is the way to go.  Also completely portable and you would need the same apple camera adapter.  It is a spectacular DAC with unbelievable quality.  The Hugo 2 is $2495.  

You can also add a 2Go which is a streamer like the Poly. Wifi, Airplay, DLNA, Roon Ready, etc... just like the Poly.  The 2Go is $1295.

There are carrying cases for both units.  

PM me if you want to discuss more or you can order direct from me at www.artaudio.us.  I am sure there are other options on the market but either of these meets your needs I think.   
As a consumer I felt when auditioning head-fi DAC/amps that Chord was overpriced when compared to similar from iFi Audio...
These are both excellent replies... thank you both! I’ll do some more research and report back here!