First things you need to get into your head when buying a crib mobile is that it is NOT a decorative piece. The crib mobile, is not an accessory to be used as the finishing touch accessory on an beautifully designed nursery. The crib mobile is actually a functioning tool in the relaxation and development of your baby.
The crib mobile also only really stays up for the first 6 months, after that, Baby can usually start grabbing at it and it can become a hazard. So, if the colors don't quite match, it's not that big a deal. It will only offend your sense of style for a few months.
Now that you know that it's okay if your mobile clashes with your decor lets get on with how to find one for you.
First let's address the questions: Is a crib mobile Necessary?
The simple answer is: No. Some babies find it a distraction, some babies don't start sleeping in their crib until they are a few months old and by then as mentioned above it is not suggested to put a mobile up because it's too much of a hazard. However, mobiles can still be placed other places like over the change table or hung from the ceiling. This guide, is not about those mobiles, this is about How to choose a crib mobile.
What to look for in a Mobile
1. Visual Stimulation
I'm amazed at how many mobiles you see in the store that look so cute in the box/on the shelf but if you were to hang it up and look at it from the bottom all you see are animal feet or car wheels. Again this is decor vs function. Most important tip which seems so obvious is look at the mobile from baby's perspective
Babymoov Jungle Mobile DIY mobile
For very young babies, experts say high contrast black and white is best because that is all they can see for the first few months. However, as they develop, colors and shapes are just as important. Ideally a mobile can have all of the above. For instance, the one pictured on the left is only for $26.99 from Wimmer-Ferguson and comes with variety of cards that you can switch out and adjust. The middle one is the Tiny Love Classic Mobile available for under $40.00 Or the one pictured on the right from Fisher Price called Link A Doos Jungle Mobile can actually be rented for $14.00 from Rent That Toy site for the duration of the time needed.
Movement is an important feature in your mobile because not only does it keep the baby interested enough to keep on watching the mobile, but it will also help stimulate baby's vision and develop hand/eye coordination. A good mobile will move horizontally AND vertically. There are all sort of mechanisms for movement: Windup, Battery, Remote Control and, kinetic. The method is really up to personal preference. Infantino Peek-A-Boo Bunny Mobile and the Tiny Love Tiny Princess Mobile both come with Remote Control and retail for under $50.00
Soft Lullabies and classical music are the best choice for relaxation. Studies have even shown that classical music helps in early development. This Fisher-Price Rainforest Peek-A-Boo Leaves Musical Mobile lets you choose from Bach, Beethoven and Mozart, while the Tiny Love Soothe 'n Groove Mobile has 18 different choices for music and sounds.
5. Longevity of a mobile
Some mobiles come with different attachments, so that even though you have to take down portions of it, other parts, like the soothing music can stay up in the crib. Or they can attach to the stroller or car seat. Like this one by Fisher Price.
I hope this helps you a little in navigating the jungle of choices out there. I am by no means the complete authority on the subject, the information shared in this post was gained from talking to Mom's I know as well as internet research. If you have notes or suggestions to add on the topic please feel free to leave a comment or email me.