You can use android apps right? For J-E, I really like Akebi
For J-J… well I haven’t used any enough to really like one. I just searched for 国語辞書 and downloaded whichever ones were free…
EDIT: Takoboto (J-E) is also recommended by the Ultimate Resource Thread…and I believe both Akebi and Takoboto can look up conjugated verbs/words, at least to some extent?