In this talk, I present the results on the time-series photometric analysis of approximately 15000 stars observed by Kepler space mission. We announce some discoveries such as solar-like oscillations in 83 red giants, 52 eclipsing binary systems etc. We have estimated the rotation periods of 2948 active stars and discuss the distribution of their frequencies and amplitudes. Interestingly, we have found star-spots in several A-type stars and observed that the number of A-type stars with starspots increases with decreasing amplitude. Using asteroseismic technique we have derived the basic astrophysical parameters such as masses, radii and luminosities of the 113 red giants. We have also found many new flares on late type stars, non-radial pulsating variables such as Delta Sct, Gamma Dor stars etc..