If you’re set on growing your nest egg for retirement, you definitely are not alone. As PC Mike Wendland reports, a number of apps can help you easily sock away money for further down the road. Acorns allows users to not only save but invest using very small amounts. Simply set Acorns up to take whatever change you are due when buying stuff and instead invest it. For example, if you spend $3.75 on a coffee, you can set Acorns to round up to $4 and invest 25 cents. The idea is that the small amounts add up over time. If you want to cash out at any time, no big…