I'm Alex, with the Shopify team!
Sure thing, there's a number of countdown and timer apps that you could check out! While there isn't actually a cart hold within Shopify - items are held only during the checkout process - timer apps can help create a sense of urgency in your store. I'd recommend checking out some of the following to see if they'd work for your needs:
For a quick view of your products, you can go about this a couple ways. There are apps that can bring in this function, such as Quick View by Secomapp or Quick Viewer. This is a feature that's also included in some premium themes, as well - if you were considering changing your theme already, you may want to check out some of the following:
Hope that's helped! There's lots more themes and apps available, so have a look around to see what might work for you. If you're not able to find one that works for you, please feel free to let me know - and you can always give us a call or start a live chat at any time. We're open 24/7 for your convenience and always happy to assist!
Alex | Shopify
Check out this video, might be of help on this... I am using it now for my site..
Which app can I install to have something like this?
and also, how can I achieve a 'quick view' when you click the item