I am trying to use Juicebox to implement some new image galleries and it works fine.
With one exception: the back button icon does not show up on mobile phones.
But it does show on my desktop and ipad.

Any ideas?

You can have a look at the gallery: www.schnek.nl/nieuw/portfolio/srilanka/index.html
These are the settings:

    showInfoButton="true"
    backButtonPosition="TOP"
    backButtonUseIcon="true"
    galleryTitlePosition="NONE"
    maxThumbColumns="8"
    enableDirectLinks="true"
    useFullscreenExpand="true"
    topAreaHeight="0"
    showSmallThumbsButton="false"
    showThumbsOnLoad="false"
    showSmallPagingText="false"
    autoPlayThumbs="false"
    shareFacebook="true"
    shareTwitter="true"
    shareGPlus="true"
    sharePinterest="true"
    shareTumblr="true"
    backButtonText="Terug naar portfolio"
    backButtonUrl="../portfolio.php"
    showImageOverlay="NEVER"
    buttonBarHAlign="CENTER"
    galleryDescription="Han Schnek fotografie www.schnek.nl"
    showOverlayOnLoad="false"
    showSmallThumbNav="true"
    showSplashPage="NEVER"
    showOpenButton="false"
    loopAudio="false"
    showExpandButton="false"
    showThumbsButton="false"
    showAutoPlayStatus="false"
    galleryTitle="Sri Lanka"
    shareUrl="http://www.schnek.nl/portfolio"

Best regards,
Han Schnek