Unfortunately, lots of people deal with tight hips and lower back problems. People who sit most of the day at work, or people who are runners are especially prone to tight hips. Here are three poses that can give you a bit of relief.
Supta Padangustasana- Start with a yoga strap (or a belt or tie will work, too). Lay on your mat. As you inhale, tilt the pelvis back so there is no space between your back and the mat. Inhale one leg up and wrap the strap around the foot. Gently pull with equal force. This stretches the hamstrings. Tight hamstrings often go hand in hand with tight hips. Stay here for about a minute, breathing deeply. Long inhales, long exhales.
Gomukasana- Start by sitting in a comfortable position. Inhale and invite the left knee over the right. Intend to get the knees stacked, but don't worry if it doesn't happen right away. Always move in a pain-free range. When you've got the knees wherever they can go, it's time for the hands.
Inhale and raise the right hand to the sky, while the left arm extends down to the ground. Exhale and bend both elbows and intend for the hands to meet. If you can hold hands, great. If not, use a strap as shown.
Baddha Konasana- Start seated with your legs out in front of you. Inhale and bring your heels as close to the pelvis as you can. Exhale the knees out to the side. Inhale and tilt the pelvis forward for a long spine. Exhale and press the feet together. Inhale and peel the feet open like a book. Do not push your knees down. Let the knees come down to wherever they can. Always keep the outer edge of the feet on the mat. Breathe here for a minute or two and gently come out.
If it's available to you, you can inhale and get taller, then exhale and send the torso forward. Always maintain a long spine when doing this.
Hope that helps!