Apple-pie order is a classic phrase used to describe a state of neatness and tidiness in a space or situation. There are several synonyms that can be used in place of this phrase, depending on the context. For example, "spick and span" is a great replacement for apple-pie order when talking about a tidy room or area. "Shipshape" also works when discussing a space that is well-organized. "Neat as a pin" is another good option when talking about a clean and orderly space. Similarly, "pristine" and "spotless" can be used in place of apple-pie order to describe something that is completely clean and free of clutter.