Whether  you're 18 or 80, managing your finances is no easy task. You might have seen your grandparents budgeting on a legal tab, or maybe your parents budget in an Excel spreadsheet. The problem with those mechanisms is that they don't provide you with any reinforcement. You can just write down your intended budget and never look at it again. Hate to break it to you: That isn't a budget.

Budgeting is a daunting task, and it really is hard to have discipline when it comes to saving, spending and investing your money. These personal finance apps are the best for your own financial management. Not only do they provide positive and negative reinforcement, but they also are a lot cooler than your grandma's legal tablet.

First and foremost, download your financial institution's account app. Every major financial institution has some form of mobile app, and most local credit unions have them now as well. It's important for you to see a total snapshot of your accounts, from savings to checking. I enjoy seeing how much my credit union pays me in interest on my savings, and I also get an email alert every time I have a withdrawal or deposit of more than $100. I know my money is safe and secure, and that way I don't have to check my account balance obsessively to make sure my account hasn't been compromised.

Mint is probably the coolest personal finance app. It does take a little time to input all your data: your checking and savings accounts, loan accounts, 401(k), etc. But how cool is it to see your entire net worth in one dashboard? Yeah, you can set up savings goals and check your account balance, but the net worth and debt account data is truly the crown jewel of this app. And you can check it on your smart phone!

While Mint is great for the long term, Level Money is great for the nitty-gritty day-to-day financial management. All you have to do is connect your checking account. Level does the rest. It automatically calculates your recurring payments and income and establishes a budget based on that information. Level determines how much you should be saving based on those amounts. The best part? All of this is done in real time for maximum efficiency.

Credit Karma is one that really helps you plan for the future based on your current credit score. It's really difficult to find a free credit score without paying money or putting your information into a sketchy website (which, by the way, you should never do). But Credit Karma is free and secure, and while it doesn't count as a credit report, it is pretty darn accurate. I downloaded this app in college and have watched my credit score increase. It's a good feeling seeing your score increase when you pay more than the minimum on your student loan. Regardless of if you have good or bad credit, it's a good idea to have a ballpark estimate of your credit score at all times.

Goodbudget is a digital version of the beloved "envelope system." I don't know about you, but I never have cash, and even though my credit union's co-op ATM is right around the corner, I'm probably just not going to go get cash for my monthly expenses. Sue me, I'm a millennial. But Goodbudget allows you to create digital envelopes and monitor your spending accordingly. If you go over your budget, you get a notification, and while that's not the same as having to put groceries back because you spent too much the week before, it still helps reinforce good spending behavior.

And lastly, Wally is another good way to track your monthly budget. If you're someone who doesn't want to sync with your checking account, or maybe your financial institution won't allow it, you can simply take a picture of your receipt instead of inputting your transaction manually. Just snap a photo and your work is done. You can also see how much you spent on a certain line item in a year. Now that's what I call convenience.

Did we miss any key personal finance apps? We'd love to hear about your favorites. Tell us!

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