Hello Alexander,
For 12th class maths you can use 12th Maths NCERT Solution for ncert maths.
Other popular apps for 12th class preparation are :

• Meritnation- it is one the most downloaded and used app by student.
• Toppr- This app is totally dedicated to 12th board class and competitive exams like JEE, NEET, MHCET. The app allows a user to set goals and helps them track their progress over the time.
• myCBSEguide

 You can use these apps and work on your studies.
I hope this information helps you.

All the best !!

Hi dear,

If you want to focus only on board then RD Sharma is enough some other notable publications are ARIHANT,KHANNA and complete mathematics by Ravi prakash.But I want to mention NCERT because this is best book which cover all topic and contain quality question.

Thank you