indyparker on "WordPress Fatal Error on Mobile Phones only"

Update -

I switched of all the plugins and tried it. Still same error on mobile devices.

Any help will be appreciated.

Here is my htaccess file:

# Wordpress htaccess

ExpiresActive On
ExpiresDefault "access plus 300 seconds"

ExpiresByType text/html "access plus 1 day"
ExpiresByType text/css "access plus 1 day"
ExpiresByType text/javascript "access plus 1 day"
ExpiresByType image/gif "access plus 1 month"
ExpiresByType image/jpg "access plus 1 month"
ExpiresByType image/png "access plus 1 month"
ExpiresByType application/x-shockwave-flash "access plus 1 day"

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>
Options All -Indexes
<files wp-config.php>
order allow,deny
deny from all
</files>

# BEGIN WPSuperCache
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
#If you serve pages from behind a proxy you may want to change 'RewriteCond %{HTTPS} on' to something more sensible
AddDefaultCharset UTF-8
RewriteCond %{REQUEST_METHOD} !POST
RewriteCond %{QUERY_STRING} !.*=.*
RewriteCond %{HTTP:Cookie} !^.*(comment_author_|wordpress_logged_in|wp-postpass_).*$
RewriteCond %{HTTP:X-Wap-Profile} !^[a-z0-9\"]+ [NC]
RewriteCond %{HTTP:Profile} !^[a-z0-9\"]+ [NC]
RewriteCond %{HTTP:Accept-Encoding} gzip
RewriteCond %{HTTPS} on
RewriteCond %{DOCUMENT_ROOT}/wp-content/cache/supercache/%{SERVER_NAME}/$1/index-https.html.gz -f
RewriteRule ^(.*) "/wp-content/cache/supercache/%{SERVER_NAME}/$1/index-https.html.gz" [L]

RewriteCond %{REQUEST_METHOD} !POST
RewriteCond %{QUERY_STRING} !.*=.*
RewriteCond %{HTTP:Cookie} !^.*(comment_author_|wordpress_logged_in|wp-postpass_).*$
RewriteCond %{HTTP:X-Wap-Profile} !^[a-z0-9\"]+ [NC]
RewriteCond %{HTTP:Profile} !^[a-z0-9\"]+ [NC]
RewriteCond %{HTTP:Accept-Encoding} gzip
RewriteCond %{HTTPS} !on
RewriteCond %{DOCUMENT_ROOT}/wp-content/cache/supercache/%{SERVER_NAME}/$1/index.html.gz -f
RewriteRule ^(.*) "/wp-content/cache/supercache/%{SERVER_NAME}/$1/index.html.gz" [L]

RewriteCond %{REQUEST_METHOD} !POST
RewriteCond %{QUERY_STRING} !.*=.*
RewriteCond %{HTTP:Cookie} !^.*(comment_author_|wordpress_logged_in|wp-postpass_).*$
RewriteCond %{HTTP:X-Wap-Profile} !^[a-z0-9\"]+ [NC]
RewriteCond %{HTTP:Profile} !^[a-z0-9\"]+ [NC]
RewriteCond %{HTTPS} on
RewriteCond %{DOCUMENT_ROOT}/wp-content/cache/supercache/%{SERVER_NAME}/$1/index-https.html -f
RewriteRule ^(.*) "/wp-content/cache/supercache/%{SERVER_NAME}/$1/index-https.html" [L]

RewriteCond %{REQUEST_METHOD} !POST
RewriteCond %{QUERY_STRING} !.*=.*
RewriteCond %{HTTP:Cookie} !^.*(comment_author_|wordpress_logged_in|wp-postpass_).*$
RewriteCond %{HTTP:X-Wap-Profile} !^[a-z0-9\"]+ [NC]
RewriteCond %{HTTP:Profile} !^[a-z0-9\"]+ [NC]
RewriteCond %{HTTPS} !on
RewriteCond %{DOCUMENT_ROOT}/wp-content/cache/supercache/%{SERVER_NAME}/$1/index.html -f
RewriteRule ^(.*) "/wp-content/cache/supercache/%{SERVER_NAME}/$1/index.html" [L]
</IfModule>

# END WPSuperCache

# BEGIN supercache
<IfModule mod_mime.c>
  <FilesMatch "\.html\.gz$">
    ForceType text/html
    FileETag None
  </FilesMatch>
  AddEncoding gzip .gz
  AddType text/html .gz
</IfModule>
<IfModule mod_deflate.c>
  SetEnvIfNoCase Request_URI \.gz$ no-gzip
</IfModule>
<IfModule mod_headers.c>
  Header set Vary "Accept-Encoding, Cookie"
  Header set Cache-Control 'max-age=3, must-revalidate'
</IfModule>
<IfModule mod_expires.c>
  ExpiresActive On
  ExpiresByType text/html A3
</IfModule>
# END supercache

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress