In just a few days, the moon will temporarily cross paths with the sun causing a total solar eclipse for part of the US.
Here are four apps that will help you plan for and view the solar eclipse on August 21st.
Solar Eclipse by Redshift provides a simulation of the solar eclipse from four different perspectives, a view from the sun, the best location, your current location, and a map view.
This simulation can help give you a better idea of what to look for during the solar eclipse as well as whether it might be worth it to make the trek to the path of totality.
You can also tinker with an eclipse calendar that will play simulations of past and future eclipses.
If you're not near the path of totality you'll still be able to view a partial solar eclipse from your location but you can also view NASA's live stream of the total eclipse from your phone with this Smithsonian Eclipse 2017 app.
This app will tell you the percentage of obscuration of the eclipse from your location, the weather forecast for the afternoon, and it provides an interactive map showing the path of totality.
On this interactive map, you can tap around and drop a pin and see the event calendar for the eclipse for that location, as well as some simulation.
Exploratorium's total solar eclipse will also provide live streams of the eclipse, along with commentary from Exploratorium educators and NASA scientists.
One hosted by Exploratorium educators in Spanish, two non-narrated telescope views from Oregon and Wyoming, and one telescope view with live music from the Kronos Quartet.
In the total solar eclipse app, you will also find reading and informational videos on eclipses, and it gives you the option to quickly add the eclipse as an event to your calendar.
If you plan to be within the path of totality, one of the most helpful apps will be the Solar Eclipse Timer app.
It's not pretty, but it will walk you through the different phases of a total eclipse with audible cues and countdown timers for the four different contact points.
Just open the app, tap check position, then tap get my location.
Using your GPS coordinates it will load the correct times for contact points, estimate the totality duration, and walk you through the eclipse.
If you only plan to view a partial solar eclipse, solar eclipse timer will not work for you.
For more tips on viewing the solar eclipse and other how tos, be sure to check out cnet.com/howto.