Unable to use form from Iphone or tablet

I am receiving continual complaints from customers that they cannot use the form or  upload files.
We are receiving an average two or three complaints everyday.

I have checked with the customers complaining and they seem to be from either phone or tablet devices the customers who are using laptops or desktop computers do not appear to be having a problem.

Are your forms compatible with phones and tablets?
If not why not over 50% of our customers now are sender or trying to send us information from these devices and this trend is growing.

We have set our forms to have a file maximum summaries of 5 MB and when we have received the uploads via e-mail all of the customers that have experienced problems the files are between 500 K and one meg so are well below our upload limit.

Customers that have told us the devices they are using are either iPhones or iPads but not all have advised us the make or model of the devices they are having difficulty with.
As we are paying for this service and we are undoubtedly losing business because it's not working properly could you please advise whether your system is compatible and if we have any settings we need to change.

I would appreciate a speedy resolution to this problem as soon as possible and your help and cooperation in trying to resolve this problem would be very much appreciated.

These forms are used on both our websites and our eBay listings.

Many thanks Barry

the form is linket to our ebay listng

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=181443599576&var=480414603822

Jotform is very compatible with mobile and was also designed for mobile users not just desktop and laptop users.

I have tested your form http://form.jotformeu.com/form/32644997492369 using an android phone and I was able to upload an image and able to submit the form.

You can view my test video here: https://shots.jotform.com/jed/vid/2014-08-22-20_12_58.rar

Possible that the problem is coming from your website not on your ebay listings since the standalone URL works fine on my end. One possible reason could be the form was embedded using a