It's true that spirituality comes from within; but technology could give you a little external nudge. With several yoga and meditation apps now available for mobile devices, instead of turning off these gadgets before beginning your sadhana, you can use them to aid your daily practice.

There are several yoga apps for the iPhone, iPod Touch and iPad available through the iTunes Store. Our personal favorite is Pocket Yoga [] ($2.99 for the iPhone, $3.99 for the iPad), which comes closest to replicating the experience of an actual yoga class. The yoga routines include clear audio instructions and images, and are customizable according to time and difficulty level. The app also tracks your practice and progress over time.

Hatha Yog [] ($4.99) works as a reference deck for various asanas, with instructions and images. A similar free app is 101 Yoga Poses [], but Hatha Yog allows you to customize your yoga routine and add songs from your iTunes music library.

The most elegantly designed is Authentic Yoga with Deepak Chopra [] ($1.99), which includes a series of videos by Dr. Chopra on the history and philosophy behind yoga. However, the app requires additional download of audio files and does not allow much customization of your yoga routine. (Update: There is now an iPad version [] as well.)

Other apps worth looking into include Chakra Deck [] (99¢), Yoga at Home (free), and Yoga Trainer Lite [] (free).

Meditation apps seem to be a more natural fit for the design and functionality of the iPhone. iSamadhi [] (99¢) is an unobtrusive meditation timer, allowing you to customize the length and focus of your meditation. Its "journal" feature records the length of your session and keeps track of your progress. Meditate ($1.99), Meditator [] ($2.99), Personal OM [] ($1.99) and My Meditation ($2.99) are similar apps, with timers, background chants, music and options for recording the length and frequency of your meditation sessions. My Meditation also allows you to regulate the timing of your breaths with gentle sounds.

Other recommended meditation apps include Om Meditation 108 [], a free app with a simple interface focused on the chanting of "Om," Simply Being [] (99¢), an excellent option for guided meditation sessions, and iMantra [] (99¢).

The Android market has only a few yoga apps, but most of them are free. Yoga by Codepalm displays yoga postures organized by category. However, since it pulls its content on demand from the Internet, it can be slow. Yoga Trainer Lite [] by [] stores its data offline, and has advanced features such as a search box and a timer. Unfortunately the current version may not be compatible with larger screens, like the Droids and the EVO 4G. Finally, the Yoga Exercises [] app by Vodafone D2 GmbH is full of nice, simple descriptions of yoga postures, and even lets you add your own! You can also share asanas through SMS and e-mail.

In the old days you could only hope to remember what your guru taught you. Now you can keep a guide in your pocket. It may seem odd that the smart phone, the symbol of shortening attention spans and constant distraction, could help in bringing peace and discipline to our lives. Perhaps. Just remember to switch your phone to airplane mode first. You don't need any texts interrupting your meditation.