We're living in the age of the app. As the catchphrase goes, "There's an app for that." It's true not only for far-flung topics like meditation, house hunting, coupon clipping, and translations for travelers, but also for small businesses.

Here are some apps that can be very handy in running your small business. See which ones you want to try -- and remember that there are many other apps aimed at small businesses that could serve you surprisingly well, too.

two hands holding a smartphone with many colorful app icons shown on it

Image source: Getty Images.

For time tracking: HoursTracker

HoursTracker can help even the smallest businesses, such as solo freelancers, keep track of their time worked. You can monitor hours worked on different projects separately, and track your pay, too, as it can incorporate  multiple pay rates. The free version of the app lets you keep track of three jobs and three weeks of work. The Personal version ($6 one-time charge) permits unlimited entries for up to five jobs, and the Pro version ($10 one-time charge) offers unlimited entries and jobs. You can tack on cloud data-storage subscriptions, too.

For billing and invoicing: Invoice by Wave

The Invoice by Wave app boasts more than two million users. It offers unlimited invoicing services for freelancers, contractors, and small businesses. The app keeps track of client details and can be set to remind you when invoices need to be sent. It can also send invoices and receipts automatically. You can add on credit card processing, too, for faster payments, with Wave Payments, which takes a small cut of each transaction. The app itself is free.

For managing projects and collaboration: Trello

Trello is a project management app that can help solo businesspeople or small businesses with multiple employees who are working together on various initiatives. It offers customized workflows and checklists, as well as the ability to upload photos, assign tasks, work offline, and much more. Trello also integrates with platforms and services such as Dropbox and Google Drive. The app is free, but you can upgrade to Trello Gold, with more bells and whistles, for $5 per month or $45 per year.

For business travel: TripIt

TripIt can be handy for any kind of travel -- business or personal. Book your flight, hotel, rental car, etc., and then forward your confirmation emails to TripIt. It will put them into a consolidated master itinerary, making it easy to look up contact information, confirmation numbers, and so on. The free version offers a lot of value, while the Pro version has more features, like real-time flight alerts, alternative-flight info, point tracking, embassy information, currency conversions, and more. The Pro version costs $49 per year.

For managing mailing lists: MailChimp

MailChimp claims to be "the world's largest marketing automation platform." It helps you manage your mailing lists and develop marketing campaigns, offering integrated ad campaigns you can run on sites like Facebook and Instagram. It gives you performance reports on your efforts, too, to help you fine-tune them. There are also templates you can adapt for your needs. The app is free.

Running a small business can be stressful and time-consuming. You can ease your burden a little with apps that do some of your work for you -- or make various tasks easier.

Selena Maranjian owns shares of Facebook. The Motley Fool owns shares of and recommends Facebook. The Motley Fool has a disclosure policy.