I thought they have a mobile app I was looking from their website but no page or link that you can download idex app.
and I found this from the support staff.
We're working on the mobile UI too with the current design. We have a new UI in the works that is having mobile professionally done too. Later on, we will have an app for IOS and Android, but that won't happen anytime soon.
At the moment IDEX is not properly supported on a mobile browser.
So it means they have a plan to make app for IOS/Android not soon but maybe in the future.
I noticed that there are some other idex app in play store but different service and feature. So I guess they are not.
Also, beware of fake phishing idex site there are many ads on google with fake idex just like this one below.