Your content has a lot of hardcoded styles and sizes, e.g.
<table style="margin: 0px; padding: 0px; border: 0px; font-family: 'Open Sans', arial, sans-serif; font-size: 13px; line-height: 21px; vertical-align: baseline; border-collapse: collapse; border-spacing: 0px; color: #555555;" width="503" cellspacing="0" cellpadding="0">
<tbody style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline;">
<tr style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline;">
<td style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; vertical-align: baseline; text-align: justify;" align="left" valign="center" width="523" height="30">
(and so on).
Try to add css style
table { width: auto !important; }
to templates/mobile_iphone/css/custom.css file (this file is intended for custom user's css styles and it is not overwritten during MJ update).
